Process for sorting objects

• US 20070203612A1
• Filed: 02/21/2007
• Published: 08/30/2007
• Est. Priority Date: 02/24/2006
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Inventors: Mileaf, Daryl S.
• Granted Patent: US 7,870,945 B2
• Time in Patent Office: Days
• US Class Current: 700/216
• CPC Class Codes: B07C 3/08 using arrangements of conveyors transport of sheets B65H; transport in general B65G
• CPC Class Codes: B07C 5/36 Sorting apparatus characterised by the means used for distribution sorting according to destination B07C3/003, B07C3/02
• CPC Class Codes: Y10S 209/90 Sorting flat-type mail

Abstract

A method for sorting objects using a continuous loop conveyor sorting system having two or more feeders. In one embodiment, the method includes sorting a batch of objects to form a first group of objects and a second group of objects, using a first feeder to feed all of the objects from the first group onto the conveyor, using a second feeder to feed all of the objects from the second group onto the conveyor, removing the objects from the first group from the conveyor prior to the any of the objects reaching the point at which the second feeder feeds objects onto the conveyor, and removing the objects from the second group from the conveyor prior to the any of the objects reaching the point at which the first feeder feeds objects onto the conveyor.

Claims

1. In an environment comprising an object sortation system comprising a conveyor, a first object feeder for feeding objects onto the conveyor, a second object feeder for feeding objects onto the conveyor, a first output section arranged between the first object feeder and the second object feeder and having a first plurality of output bins, and a second output section positioned downstream from the second object feeder and having a second plurality of output bins, wherein the conveyor is configured to convey objects such that an object fed onto the conveyor by the first object feeder must first pass the first output section prior to passing the point at which the second object feeder feeds objects onto the conveyor, a method comprising the steps of:

obtaining a plurality of objects comprising a first subset of objects and a second subset of objects, wherein each object within the first subset of objects has a first attribute and each object within the second subset of objects has a second attribute;

assigning to the first output section all of the objects of said first subset of objects;

assigning to the second output section all of the objects of said second subset of objects;

positioning the objects having the first attribute at an input of the first object feeder;

positioning the objects having the second attribute at an input of the second object feeder;

using the first object feeder to feed onto the conveyor each of said objects having the first attribute;

using the second object feeder to feed onto the conveyor each of said objects having the second attribute;

using the conveyor to convey each of said objects having the first attribute to the first output section, wherein each of said objects having the first attribute reaches said first output section without having passed the point at which the second object feeder feeds objects onto the conveyor;

using the conveyor to convey each of said objects having the second attribute to the second output section, wherein each of said objects having the second attribute reaches said second output section without having passed the point at which the first object feeder feeds objects onto the conveyor;

when an object having the first attribute is adjacent an output bin of the first output section, removing the object from the conveyor and placing the object in the output bin; and

when an object having the second attribute is adjacent an output bin of the second output section, removing the object from the conveyor and placing the object in the output bin.

2. The method of claim 1, wherein said plurality of objects further comprises a third subset of objects and a fourth subset of objects, wherein each object within the third subset of objects has a third attribute and each object within the fourth subset of objects has a fourth attribute.

3. The method of claim 1, further comprising:

using the first object feeder to feed onto the conveyor each of said objects having the third attribute after using said first object feeder to feed all of said objects having the first attribute onto the conveyor;

using the second object feeder to feed onto the conveyor each of said objects having the fourth attribute after using the second object feeder to feed all of said objects having the second attribute onto the conveyor.

4. The method of claim 3, further comprising:

using the conveyor to convey each of said objects having the third attribute to the first output section, wherein each of said objects having the third attribute reaches said first output section without having passed the point at which the second object feeder feeds objects onto the conveyor;

using the conveyor to convey each of said objects having the fourth attribute to the second output section, wherein each of said objects having the fourth attribute reaches said second output section without having passed the point at which the first object feeder feeds objects onto the conveyor;

when an object having the third attribute is adjacent an output bin of the first output section, removing the object from the conveyor and placing the object in the output bin; and

when an object having the fourth attribute is adjacent an output bin of the second output section, removing the object from the conveyor and placing the object in the output bin.

5. The method of claim 1, wherein the conveyor is in the form of a closed loop.

6. The method of claim 1, wherein the step of removing an object from the conveyor comprises using a tilt tray or cross belt to remove said object from the conveyor.

7. A system comprising:

sorting means for separating a plurality of objects into at least a first subset of objects and a second subset of objects, wherein each object within the first subset shares a common first attribute, and each object within the second subset shares a common second attribute;

a first feeding means for feeding the first subset of objects onto a conveyor;

a second feeding means for feeding the second subset of objects onto the conveyor;

a first discharge station; and

a second discharge station, wherein

the conveyor is configured to (a) transport the first subset of objects to the first discharge station such that each of said first subset of objects reaches the first discharge station without passing the point at which the second object feeder introduces objects onto the conveyor and (b) transport the second subset of objects to the second discharge station such that each of said second subset of objects reaches the second discharge station without passing the point at which the first object feeder introduces objects onto the conveyor,

the first discharge station comprises object removing means for removing from said conveyor each of the objects included within the first subset of objects so that each of the objects included within the first subset of objects will not reach the point at which the second object feeder introduces objects onto the conveyor, and

the second discharge station comprises object removing means for removing from said conveyor each of the objects included within the second subset of objects so that each of the objects included within the second subset of objects will not reach the point at which the first object feeder introduces objects onto the conveyor.

8. The system of claim 7, wherein the sorting means comprises a continuous loop conveyor path, two or more feeders, and two or more output sections.

9. The system of claim 7, wherein the first feeding means comprises a feeder configured to feed mail or parcels onto the conveyor.

10. The system of claim 7, wherein the object removing means comprises a tilt tray.

11. The system of claim 7, wherein the object removing means comprises a cross belt.

12. The system of claim 7, wherein the conveyor is a continuous loop conveyor.

13. A method for sorting objects, comprising:

obtaining a batch of objects;

sorting the batch of objects to form at least a first group of objects and a second group of objects;

after forming the first and second groups of objects, for each object within the first group of objects, (i) using a first feeder to feed the object onto a continuous loop conveyor, (ii) using the conveyor to transport the object to a first output section that is disposed downstream from the first feeder and upstream from a second feeder, and (iii) removing the object from the conveyor while the object is adjacent the first output section and placing the object in an output bin of the first output section so that the object will not reach the point on the conveyor at which the second feeder deposits objects onto the conveyor; and

after forming the first and second groups of objects, for each object within the second group of objects, (i) using the second feeder to feed the object onto a continuous loop conveyor, (ii) using the conveyor to transport the object to a second output section that is disposed downstream from the second feeder and upstream from the first feeder, and (iii) removing the object from the conveyor while the object is adjacent the second output section and placing the object in an output bin of the second output section so that the object will not reach the point on the conveyor at which the first feeder deposits objects onto the conveyor.

14. The method of claim 13, wherein the step of using the second feeder to feed the objects from the second group of objects onto the continuous loop conveyor is performed concurrently with the step of using the first feeder to feed the objects from the first group of objects onto the continuous loop conveyor.

15. The method of claim 13, comprising:

sorting the batch of objects to form a third group of object and a fourth group of objects in addition to the first group of objects and the second group of objects.

16. The method of claim 15, comprising:

after forming the third group of objects, for each object within the third group of objects, (i) using a third feeder to feed the object onto the continuous loop conveyor, (ii) using the conveyor to transport the object to a third output section that is disposed downstream from the third feeder and upstream from the first feeder, the second feeder and a fourth feeder, and (iii) removing the object from the conveyor while the object is adjacent the third output section and placing the object in an output bin of the third output section so that the object will not pass the third output section; and

after forming the fourth group of objects, for each object within the fourth group of objects, (i) using the fourth feeder to feed the object onto the continuous loop conveyor, (ii) using the conveyor to transport the object to a fourth output section that is disposed downstream from the fourth feeder and upstream from the first feeder, the second feeder and the third feeder, and (iii) removing the object from the conveyor while the object is adjacent the fourth output section and placing the object in an output bin of the fourth output section so that the object will not pass the fourth output section.

17. The method of claim 15, comprising:

after all of the objects within the first group of objects have been deposited onto the conveyor, for each object within the third group of objects, (i) using the first feeder to feed the object onto the continuous loop conveyor, (ii) using the conveyor to transport the object to the first output section, and (iii) removing the object from the conveyor while the object is adjacent the first output section and placing the object in an output bin of the first output section so that the object will not reach the point on the conveyor at which the second feeder deposits objects onto the conveyor.

18. The method of claim 17, comprising:

after all of the objects within the second group of objects have been deposited onto the conveyor, for each object within the fourth group of objects, (i) using the second feeder to feed the object onto the continuous loop conveyor, (ii) using the conveyor to transport the object to the second output section, and (iii) removing the object from the conveyor while the object is adjacent the second output section and placing the object in an output bin of the second output section so that the object will not reach the point on the conveyor at which the first feeder deposits objects onto the conveyor.

19. The method of claim 18, wherein the step of using the second feeder to feed the objects from the fourth group of objects onto the continuous loop conveyor is performed concurrently with the step of using the first feeder to feed the objects from the third group of objects onto the continuous loop conveyor.

20. The method of claim 19, wherein the batch of objects comprises a plurality of parcels.