Bubble up auger for combine harvester

1. A bubble-up auger for an agricultural vehicle, said bubble-up auger comprising:

a unitary rotatable shaft;

a lower auger section either mounted to or forming part of the unitary rotatable shaft;

an upper auger section that is removably connected to the lower auger section, and includes an opening through which the unitary rotatable shaft is at least partially positioned, wherein the upper auger section is moveable between a first position where the upper auger section is detached from the lower auger section and a second position where the upper auger section is connected to the lower auger section,

wherein the lower auger section comprises (i) a lower auger tube having two opposing ends and a passage extending between the ends through which the unitary rotatable shaft is positioned, (ii) a first coupling being disposed at one of the two opposing ends and non-rotatably connecting the unitary rotatable shaft to the lower auger tube, and (iii) a second coupling being mounted at the other of the two opposing ends and non-rotably connected to the lower auger tube, wherein the unitary rotatable shaft passes through an opening in the second coupling,

wherein the upper auger section comprises an upper auger tube having two opposing ends, and a third coupling mounted at one of the two opposing ends,

wherein, when the upper auger section is maintained in the second position, the third coupling is at least partially non-rotatably connected to the second coupling and the unitary rotatable shaft passes through an opening in the third coupling such that the unitary rotatable shaft is at least partially positioned within the upper auger tube.

2. The bubble-up auger of claim 1 , wherein the auger does not include a bearing at an intersection between the lower auger section and the upper auger section.

3. The bubble-up auger of claim 1 , wherein the first coupling is non-rotatably connected to the unitary rotatable shaft by a splined connection.

4. The bubble-up auger of claim 1 , wherein the lower auger tube is slideably connected to the unitary rotatable shaft by a sliding fit connection.

5. The bubble-up auger of claim 1 further comprising a tooth extending from the second coupling, wherein the tooth is configured to interact with a tooth extending from the upper auger section, wherein each tooth includes a free end in the form of an angled surface.

6. The bubble-up auger of claim 1 , wherein the third coupling includes an interior surface having a chamfer or a counterbore for accommodating movement of the third coupling with respect to a free end of the unitary rotatable shaft.

7. The bubble-up auger of claim 1 , wherein the upper and lower auger sections each include flightings, wherein the flightings of the upper auger section is positioned directly adjacent the flightings of the lower auger section.

8. The bubble-up auger of claim 7 , wherein no bearings are positioned between the flightings of the upper and lower auger sections.

9. The bubble-up auger of claim 1 further comprising a bevel gear set, wherein one of the gears of the bevel gear set is either connected to or forms part of the unitary rotatable shaft.

10. The bubble-up auger of claim 9 , further comprising a housing defining an interior space in which the bevel gear set is at least partially positioned.

11. The bubble-up auger of claim 10 further comprising bearings positioned within the housing, wherein one bearing is associated with one gear of the bevel gear set, and another bearing is associated with the other gear of the bevel gear set.

12. The bubble-up auger of claim 10 wherein the unitary rotatable shaft is at least partially mounted within the housing.

13. An agricultural harvester comprising the bubble-up auger of claim 1 .

14. A grain tank for the agricultural vehicle comprising the bubble-up auger of claim 1 .