Rotary sickle cutting system for an agricultural vehicle having a plurality of cutting units with a rotatable disc and guard assembly

1. An agricultural vehicle, comprising:

a chassis;

a header carried by the chassis, the header including a cutterbar assembly with a plurality of cutting units, each of the cutting units including:

a rotatable disc carrying a plurality of knives each defining at least one cutting edge; and

a guard assembly including a plurality of extensions, each of the extensions including a bottom guard portion connected to a top guard portion to define a knife slot that allows the plurality of knives to pass through during rotation of the disc; and

at least one rotary driver coupled to the rotatable disc of at least one of the cutting units,

wherein the plurality of cutting units include a first cutting unit and a second cutting unit, the first cutting unit and the second cutting unit being positioned such that the plurality of knives of the first cutting unit define a first rotational region and the plurality of knives of the second cutting unit define a second rotational region that partially overlaps the first rotational region.

2. The agricultural vehicle of claim 1 , wherein each of the extensions is laterally spaced apart from at least one other adjacent extension to define a crop slot therebetween.

3. The agricultural vehicle of claim 1 , wherein the top guard portion is cantilevered to the bottom guard portion.

4. The agricultural vehicle of claim 1 , wherein the plurality of cutting units are positioned side-by-side across a width of the header.

5. The agricultural vehicle of claim 1 , wherein the plurality of knives of the first cutting unit are vertically offset from the plurality of knives of the second cutting unit.

6. The agricultural vehicle of claim 1 , wherein each of the plurality of cutting units includes at least three knives.

7. The agricultural vehicle of claim 1 , wherein each of the rotatable discs is rotatably connected to an associated rotary driver.

8. The agricultural vehicle of claim 1 , wherein the plurality of knives extend radially from a circumference of the rotatable disc.

9. The agricultural vehicle of claim 1 , wherein the first cutting unit includes a first bottom guard portion connected to a second bottom guard portion of the second cutting unit.

10. A header for an agricultural vehicle, comprising:

a header frame;

a cutterbar assembly with a plurality of cutting units carried by the header frame, each of the cutting units including:

a rotatable disc carrying a plurality of knives each defining at least one cutting edge; and

a guard assembly including a plurality of extensions, each of the extensions including a bottom guard portion connected to a top guard portion to define a knife slot that allows the plurality of knives to pass through during rotation of the disc; and

at least one rotary driver coupled to the rotatable disc of at least one of the cutting units,

wherein the plurality of cutting units include a first cutting unit and a second cutting unit, and the plurality of knives of the first cutting unit are vertically offset from the plurality of knives of the second cutting unit.

11. The header of claim 10 , wherein each of the extensions is laterally spaced apart from at least one other adjacent extension to define a crop slot therebetween.

12. The header of claim 10 , wherein the top guard portion is cantilevered to the bottom guard portion.

13. The header of claim 10 , wherein the plurality of cutting units are positioned side-by-side across a width of the header frame.

14. The header of claim 13 , wherein the first cutting unit and the second cutting unit are positioned such that the plurality of knives of the first cutting unit define a first rotational region and the plurality of knives of the second cutting unit define a second rotational region that partially overlaps the first rotational region.

15. The header of claim 10 , wherein each of the plurality of cutting units includes at least three knives.

16. The header of claim 10 , wherein each of the rotatable discs is rotatably connected to an associated rotary driver.

17. The header of claim 10 , wherein the plurality of knives extend radially from a circumference of the rotatable disc.

18. The header of claim 10 , wherein the first cutting unit includes a first guard assembly connected to a second guard assembly of the second cutting unit.

19. A header for an agricultural vehicle, comprising:

a header frame;

a cutterbar assembly with a plurality of cutting units carried by the header frame, each of the cutting units including:

a rotatable disc carrying a plurality of knives each defining at least one cutting edge; and

a guard assembly including a plurality of extensions, each of the extensions including a bottom guard portion connected to a top guard portion to define a knife slot that allows the plurality of knives to pass through during rotation of the disc, and wherein the top guard portion includes a sharpened edge; and

at least one rotary driver coupled to the rotatable disc of at least one of the cutting units.

20. The header of claim 19 , wherein the plurality of cutting units include a first cutting unit and a second cutting unit, the first cutting unit and the second cutting unit being positioned such that the plurality of knives of the first cutting unit define a first rotational region and the plurality of knives of the second cutting unit define a second rotational region that partially overlaps the first rotational region, and wherein the plurality of knives of the first cutting unit are vertically offset from the plurality of knives of the second cutting unit.