Debris removal system for an agricultural harvester and related extractors

1. A debris removal system for an agricultural harvester, the debris removal system comprising:

a chopper assembly configured to chop harvested crops into billets;

an elevator configured to receive a stream of billets from the chopper assembly;

an extractor configured to remove debris separated from the billets, the extractor including an extractor housing defining a central airflow channel for directing the debris through the extractor from a central inlet of the housing to a central outlet of the housing, the extractor housing further defining an outer airflow channel surrounding the central airflow channel, the outer airflow channel defining a flow path between an outer housing inlet and an outer airflow outlet of the housing, the extractor housing including an internal divider wall extending between the central airflow channel and the outer airflow channel; and

at least one flow-generating device provided in operative association with the housing, the at least one flow-generating device generating an airflow directed through the flow path defined by the outer airflow channel,

wherein the airflow generates a negative pressure within the central airflow channel that draws the debris into the extractor housing via the central airflow inlet,

wherein the internal divider wall defines a boundary between the central airflow channel and the outer airflow channel such that the internal divider wall separates the debris drawn through the central airflow channel from the airflow directed through the flow path defined by the outer airflow channel.

2. The debris removal system of claim 1 , wherein the divider wall extends between a bottom end positioned at or adjacent to an inner surface of an outer housing wall of the housing and a top end spaced apart from the inner surface of the outer housing wall, the top end of the divider wall dividing the central outlet from the outer airflow outlet within an interior of the housing.

3. The debris removal system of claim 2 , wherein the divider wall converges radially inwardly as the divider wall extends from its bottom end to its top end such that a diameter of the central airflow channel decreases between the bottom and top ends of the divider wall.

4. The debris removal system of claim 1 , wherein the central airflow channel and the outer airflow channel are concentrically aligned with a central axis of the extractor housing.

5. The debris removal system of claim 1 , wherein the outer housing outlet is defined through an outer housing wall of the housing forming an outer perimeter of the extractor, the at least one flow-generating device being provided in flow communication with the outer housing outlet along the outer perimeter of the extractor.

6. The debris removal system of claim 5 , wherein the at least one flow-generating device comprises at least one blower configured to generate the airflow through the outer airflow channel.

7. The debris removal system of claim 6 , wherein the at least one blower comprises a plurality of blowers spaced apart circumferentially from one another around the outer perimeter of the extractor.

8. The debris removal system of claim 5 , wherein the at least one flow-generating device comprises at least one axial-flow fan assembly configured to generate the airflow through the outer airflow channel.

9. The debris removal system of claim 8 , wherein the at least one axial-flow fan assembly is installed within the outer housing inlet defined through the outer housing wall of the housing.

10. The debris removal system of claim 8 , further comprising a plurality of outer housing inlets defined through the outer housing wall of the housing, the at least one axial-flow fan assembly comprising a plurality of axial-flow fan assemblies spaced apart circumferentially from one another around the outer perimeter of the extractor housing, each axial-flow fan assembly being installed within a corresponding outer housing inlet of the plurality of outer housing inlets.

11. The debris removal system of claim 1 , wherein the at least one flow-generating device is positioned within the outer airflow channel along the flow path defined between the outer housing inlet and outer airflow outlet.

12. The debris removal system of claim 11 , wherein the at least one flow-generating device comprises at least one axial-flow fan assembly positioned within the outer airflow channel.

13. The debris removal system of claim 11 , further comprising a support structure configured to support the at least one flow-generating device positioned within the outer airflow channel.

14. The debris removal system of claim 1 , wherein the extractor comprises a primary extractor or a secondary extractor for the agricultural harvester.

15. An extractor for removing debris from crops harvested by an agricultural harvester, the extractor comprising:

an extractor housing defining a central airflow channel through which debris is directed from a central inlet of the housing to a central outlet of the housing, the extractor housing further defining an outer airflow channel surrounding the central airflow channel, the outer airflow channel defining a flow path between an outer housing inlet and an outer airflow outlet of the housing, the extractor housing including an internal divider wall extending between the central airflow channel and the outer airflow channel; and

at least one flow-generating device provided in operative association with the housing, the at least one flow-generating device generating an airflow directed through the flow path defined by the outer airflow channel,

wherein the airflow generates a negative pressure within the central airflow channel that is configured to draw the debris into the extractor housing via the central airflow inlet,

wherein the internal divider wall defines a boundary between the central airflow channel and the outer airflow channel such that the internal divider wall separates the debris drawn through the central airflow channel from the airflow directed through the flow path defined by the outer airflow channel.

16. The extractor of claim 15 , wherein the divider wall extends between a bottom end positioned at or adjacent to an inner surface of an outer housing wall of the housing and a top end spaced apart from the inner surface of the outer housing wall, the top end of the divider wall dividing the central outlet from the outer airflow outlet within an interior of the housing.

17. The extractor of claim 16 , wherein the divider wall converges radially inwardly as the divider wall extends from its bottom end to its top end such that a diameter of the central airflow channel decreases between the bottom and top ends of the divider wall.

18. The extractor of claim 15 , wherein the at least one flow-generating device comprises at least one blower provided in flow communication with the outer housing inlet along an outer perimeter of the extractor.

19. The extractor of claim 15 , wherein the at least one flow-generating device comprises at least one axial-flow fan assembly installed within the outer housing inlet or within the outer airflow channel.

20. The extractor of claim 15 , wherein the extractor comprises a primary extractor or a secondary extractor for the agricultural harvester.