Agricultural toolbar apparatus, systems, and methods

1. A toolbar of an agricultural implement, comprising:

a left member of the toolbar of the agricultural implement;

a right member of the toolbar of the agricultural implement; and

a synchronizing mechanism by which said left member and said right member of the toolbar of the agricultural implement are pivotally engaged and constrained so as to transfer pivotal forces between them such that said left and right members pivot symmetrically and synchronously with respect to one another about a vertical longitudinal plane;

a left wing section having a first plurality of ground-engaging tools mounted thereto;

a right wing section having a second plurality of ground-engaging tools mounted thereto, wherein said toolbar has a field position in which said wing sections extend generally transversely and a transport position in which said wing sections extend generally longitudinally, and wherein as the toolbar folds from said field position to said transport position, a proximal end of each said wing section moves rearward relative to the tractor and a distal end of each said wing section moves inward;

wherein said left wing section is pivotally coupled to the toolbar at a left horizontal pivot axis, wherein said left horizontal pivot axis extends generally longitudinally, wherein said right wing section is pivotally coupled to the toolbar at a right horizontal pivot axis, wherein said right horizontal pivot axis extends generally longitudinally, wherein said left member is pivotally coupled to the toolbar at a left outboard pivot axis, and wherein said right member is pivotally coupled to the toolbar about a right outboard pivot axis; and

wherein said left outboard pivot axis is located outboard of said left horizontal pivot axis when the toolbar is in said field position, and wherein said right outboard pivot axis is located outboard of said right horizontal pivot axis when the toolbar is in said field position.

2. The agricultural toolbar of claim 1 , further comprising:

a left inner wing section pivotally coupled to said center bar for pivoting about a generally vertical axis; and

a right inner wing section pivotally coupled to said center bar for pivoting about a generally vertical axis.

3. The agricultural toolbar of claim 2 , further comprising:

a left dogleg rigidly mounted to said left inner wing section, said left dogleg extending generally transversely; and

a right dogleg rigidly mounted to said right inner wing section, said right dogleg extending generally transversely, wherein said left member is pivotally coupled to said left dogleg, and wherein said right member is pivotally coupled to said right dogleg.

4. The agricultural toolbar of claim 2 , further comprising:

a left wing actuator disposed to transfer a moment between said left inner wing section and said left wing section; and

a right wing actuator disposed to transfer a moment between said right inner wing section and said right wing section.

5. The agricultural toolbar of claim 4 , wherein said left wing actuator is in fluid communication with a pressure control valve.

6. The agricultural toolbar of claim 5 , further including:

processing circuitry configured to modify a pressure set by said pressure control valve, wherein said pressure control valve is in electrical communication with said processing circuitry.

7. An agricultural toolbar, comprising:

a longitudinally extending weight transfer frame; and

a weight transfer actuator disposed to transfer weight between a tractor and the toolbar, said weight transfer actuator pivotally coupled to said weight transfer frame, wherein said weight transfer actuator is in fluid communication with a pressure control valve, wherein said pressure control valve is configured to select a pressure in said weight transfer actuator;

processing circuitry configured to modify a pressure set by said pressure control valve, wherein said pressure control valve is in electrical communication with said processing circuitry;

wherein said weight transfer actuator is a dual-acting hydraulic cylinder, wherein when the weight transfer actuator applies force in a first direction, weight is transferred from the toolbar to the tractor, and wherein when the weight transfer actuator applies force in a second direction, weight is transferred from the tractor to the toolbar.

8. The agricultural toolbar of claim 7 , further including:

a transversely extending center bar;

a latch configured to latch said center bar to said weight transfer frame;

a latch actuator configured to selectively engage said latch; and

a directional control valve located in a cab of the tractor, wherein said weight transfer actuator is in fluid communication with said directional control valve, whereby an operator is enabled to selectively latch said center bar to said weight transfer frame by manipulating said directional control valve.

9. The agricultural toolbar of claim 7 , further including:

a left wing section having a first plurality of ground-engaging tools mounted thereto; and

a right wing section having a second plurality of ground-engaging tools mounted thereto, wherein said toolbar has a field position in which said wing sections extend generally transversely and a transport position in which said wing sections extend generally longitudinally, and wherein as the toolbar folds from said field position to said transport position, said center bar moves rearward relative to the tractor and a distal end of each said wing section moves inward.

10. The agricultural toolbar of claim 9 , further comprising:

a left wing actuator disposed to impose a moment on said left wing section; and

a right wing actuator disposed to impose a moment on said right wing section.

11. The agricultural toolbar of claim 10 , wherein said left wing actuator is in fluid communication with a wing actuator pressure control valve.

12. The agricultural toolbar of claim 11 , further including:

processing circuitry configured to modify a pressure set by said wing actuator pressure control valve, wherein said pressure control valve is in electrical communication with said processing circuitry.

13. A method of transferring weight between a tractor and an agricultural toolbar, comprising:

determining a net toolbar ground force acting on a plurality of toolbar wheels supporting the toolbar;

determining an estimated tractor weight carried by the rear tractor wheels of the tractor based on a user input;

determining an estimated tractor weight transfer amount transferred between the tractor and the toolbar based on a pressure in an actuator configured to transfer weight between the tractor and the toolbar;

calculating a net tractor ground force by adding said weight transfer amount to said estimated tractor weight;

comparing said net tractor ground force to said net toolbar ground force; and

modifying a pressure in said actuator so that said net toolbar ground force more closely approximates said net tractor ground force.

14. The method of claim 13 , further including:

applying a multiplier to the net tractor ground force before comparing said net tractor ground force to said net toolbar ground force.

15. The method of claim 14 , wherein said multiplier is based on a user input.

16. The method of claim 15 , wherein said multiplier is based on a first factor related to the agronomic damage by said tractor wheels per pound of ground force applied to said tractor wheels and a second factor related to the agronomic damage by said toolbar wheels per pound of ground force applied to said toolbar wheels.

17. The method of claim 16 , wherein said multiplier is based on a ratio between said first factor and said second factor.

18. The method of claim 13 , wherein said toolbar wheels support a center section of the toolbar, further including:

applying a left wing moment to a left wing section pivotally coupled to said center section;

applying a right wing moment to a right wing section pivotally coupled to said center section;

determining a right wing wheel ground force acting on a right wing wheel supporting said right wing section at a distal end;

determining a left wing wheel ground force acting on a left wing wheel supporting said left wing section at a distal end;

comparing said left wing wheel ground force to a first desired value;

comparing said right wing wheel ground force to second desired value;

modifying said left wing moment such that said left wing wheel ground force more closely approximates said first desired value; and

modifying said right wing moment such that said right wing wheel ground force more closely approximates said second desired value.

19. The method of claim 18 , wherein said first desired value and said second desired value are predetermined constant values.

20. The method of claim 18 , wherein said first desired value and said second desired value are based on one or more user inputs.

21. The method of claim 18 , wherein said first desired value and said second desired value are based on a ratio between agronomic damage caused by weight on the toolbar wheels and agronomic damage caused by weight on the wing wheels.

22. The method of claim 20 , wherein said first desired value and said second desired value are based on a ratio between agronomic damage caused by weight on the toolbar wheels and agronomic damage caused by weight on the wing wheels.