Seed firmer and planting machine

1. A seed firmer for a planting machine, the seed firmer comprising:

an attachment bracket having a portion provided for attachment to a row unit of the planting machine;

a non-compliant arm provided with a ground-facing surface for engagement with the soil during planting; and

a mount through which the non-compliant arm is connected to the attachment bracket,

wherein the mount is a compliant mount operable to deflect and exert an elastic bias force during operation, without deflection of the non-compliant arm,

wherein the mount is provided by a linkage comprising a first link having a first end pivotally coupled to the attachment bracket and a second end pivotally coupled to the non-compliant arm, and a second link having a first end pivotally coupled to the attachment bracket and having a second end pivotally coupled to the non-compliant arm, and

wherein the first and second links are normally biased to have a parallel relationship, and wherein one of the first and second links includes a selective sliding joint operable to enable the linkage to be selectively tripped to transition from the parallel relationship to a non-parallel relationship.

2. The seed firmer of claim 1 , wherein the mount includes a spring.

3. The seed firmer of claim 1 , wherein, when in the parallel relationship, the first link and the second link, along with the non-compliant arm and a base link fixed with respect to the attachment bracket, form a parallel linkage so that the non-compliant arm is movable relative to the attachment bracket without changing orientation.

4. The seed firmer of claim 1 , wherein the elastic bias force is provided by a spring, the seed firmer further comprising a second spring operable to bias the selective sliding joint into a position that maintains the parallel relationship between the first and second links.

5. A seed firmer for a planting machine, the seed firmer comprising:

an attachment bracket having a portion provided for attachment to a row unit of the planting machine;

a non-compliant arm provided with a ground-facing surface for engagement with the soil during planting; and

a mount through which the non-compliant arm is connected to the attachment bracket,

wherein the mount is a compliant mount operable to deflect and exert an elastic bias force during operation, without deflection of the non-compliant arm,

wherein the elastic bias force is provided by a spring held in tension throughout an entire range of motion of the non-compliant arm, the range of motion of the non-compliant arm being limited by an abutment surface of the mount,

the seed firmer further comprising a pivot connection between the non-compliant arm and the mount, wherein the abutment surface and the pivot connection are provided by parallel, spaced pins extending between lateral side plates of the mount that flank the non-compliant arm.

6. A seed firmer for a planting machine, the seed firmer comprising:

an attachment bracket having a portion provided for attachment to a row unit of the planting machine;

a non-compliant arm provided with a ground-facing surface for engagement with the soil during planting;

a mount through which the non-compliant arm is connected to the attachment bracket,

wherein the mount is a compliant mount operable to deflect and exert an elastic bias force during operation, without deflection of the non-compliant arm; and

a pivot connection between the non-compliant arm and the mount, wherein the pivot connection defines an axis for the relative rotation between the non-compliant arm and the mount that is fixed relative to the non-compliant arm and the mount, and wherein the pivot connection is positioned along the non-compliant arm at a location between the ground-facing surface and a portion of the non-compliant arm to which a spring providing the elastic bias force is attached.

7. A planting machine comprising:

a plurality of row units, each row unit having a furrow opener, furrow closing wheels behind the opener, a seed dispensing cartridge between the opener and the closing wheels, and a seed firmer coupled to the row unit behind the cartridge and forward of the closing wheels,

wherein the seed firmer in each of the plurality of row units has a non-compliant arm and a compliant mount coupling the arm to the row unit, and

wherein the compliant mount is provided by a linkage comprising a first link having a first end pivotally coupled to an attachment bracket of the seed firmer and a second end pivotally coupled to the non-compliant arm, and a second link having a first end pivotally coupled to the attachment bracket and having a second end pivotally coupled to the non-compliant arm.

8. The planting machine of claim 7 , wherein the compliant mount includes a spring.

9. The planting machine of claim 7 , wherein the first link and the second link, along with the non-compliant arm and a base link fixed with respect to the attachment bracket, form a parallel linkage so that the non-compliant arm is movable relative to the attachment bracket without changing orientation.

10. The planting machine of claim 7 , wherein the first and second links are normally biased to have a parallel relationship, and wherein one of the first and second links includes a selective sliding joint operable to enable the linkage to be selectively tripped to transition from the parallel relationship to a non-parallel relationship.

11. The planting machine of claim 10 , wherein the compliant mount includes a first spring operable to bias the non-compliant arm groundward, wherein the seed firmer further includes a second spring operable to bias the selective sliding joint into a position that maintains the parallel relationship between the first and second links.

12. A planting machine comprising:

a plurality of row units, each row unit having a furrow opener, furrow closing wheels behind the opener, a seed dispensing cartridge between the opener and the closing wheels, and a seed firmer coupled to the row unit behind the cartridge and forward of the closing wheels

wherein the seed firmer in each of the plurality of row units has a non-compliant arm and a compliant mount coupling the arm to the row unit, and

wherein the seed firmer includes a spring held in tension throughout an entire range of motion of the non-compliant arm, the range of motion of the non-compliant arm being limited by an abutment surface of the compliant mount.

13. The planting machine of claim 12 , further comprising a pivot connection between the non-compliant arm and the compliant mount, wherein the abutment surface and the pivot connection are provided by parallel, spaced pins extending between lateral side plates of the compliant mount that flank the non-compliant arm.

14. A planting machine comprising:

a plurality of row units, each row unit having a furrow opener, furrow closing wheels behind the opener, a seed dispensing cartridge between the opener and the closing wheels, and a seed firmer coupled to the row unit behind the cartridge and forward of the closing wheels,

wherein the seed firmer in each of the plurality of row units has a non-compliant arm, a compliant mount coupling the arm to the row unit, and a pivot connection between the non-compliant arm and the compliant mount.

15. The planting machine of claim 14 , wherein the pivot connection defines an axis for the relative rotation between the non-compliant arm and the compliant mount that is fixed relative to the non-compliant arm and the compliant mount, and wherein the pivot connection is positioned along the non-compliant arm at a location between the ground-facing surface and a portion of the non-compliant arm to which a spring that biases the non-compliant arm groundward is attached.