Tillage implement with enhanced front wheel suspension

Patent metadata

Field	Value
Publication number	US-9781872-B2
Application number	US-201414468092-A
Country	US
Kind code	B2
Filing date	Aug 25, 2014
Priority date	Aug 26, 2013
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A tillage implement has a main frame provided with power-actuated lift wheels at the rear of the frame and a pair of gauge wheels at the front of the frame. A linkage system connecting the rear wheels with the front wheels transmits the raising and lowering motion of the rear wheels to the front wheels so that the main frame remains level as it is raised and lowered by all of the wheels in unison. However, a coupling that uses an equalizing rocker bar between front and rear linkages of the linkage system permits either of the front wheels to be raised or lowered in a non-corresponding manner relative to the other front wheel as differences in terrain contour are experienced between the two front wheels. During such non-corresponding shifting of the front wheels relative to one another, movement of the two front wheels is in equal amounts but opposite directions to maintain both front wheels engaging the ground at all times and equally sharing the load.

First claim

The invention claimed is:

1. A tillage implement comprising:
a substantially rigid main frame;
a floating hitch coupled to and extending forwardly from a front portion of said main frame with respect to a direction of travel of the main frame;
left and right front wheels positioned on opposite sides of an imaginary centerline of said main frame;
left and right rear wheels positioned on opposite sides of said imaginary centerline of said main frame;
a rear wheel support system coupling said left and right rear wheels to said frame; and
a front wheel support system coupling said left and right front wheels to said main frame,
wherein said front wheel support system is configured to allow non-corresponding shifting of said right and left front wheels relative to said main frame,
wherein said implement comprises a mechanical linkage system coupling said front and rear wheel support systems in a manner such that shifting of said rear wheels relative to said main frame causes shifting of said front wheels relative to said main frame,
said mechanical linkage system coupling said left and right front wheels in a manner such that shifting of one of said front wheels relative to said main frame causes shifting of the other of said front wheels relative to said main frame,
wherein said front wheel support system comprises a left front wheel support system for supporting said left front wheel and a right front wheel support system for supporting said right front wheel,
wherein said mechanical linkage system comprises a rocker bar configured to pivot relative to said main frame on a substantially upright rocker pivot axis,
said left and right front wheel support systems being mechanically linked to said rocker bar on opposite sides of said rocker pivot axis.

2. A tillage implement as claimed in claim 1 ,
wherein said rear wheel support system is shiftable relative to said main frame,
said rear wheel support system being mechanically linked to said rocker bar in a manner such that shifting of said rear wheel support system causes forward or rearward movement of said entire rocker bar, thereby causing forward or rearward movement of said rocker pivot axis.

3. A tillage implement as claimed in claim 2 ,
wherein said rear wheel support system comprises a torque bar, a left rear wheel support arm coupled to one end of said torque bar, and a right rear wheel support arm coupled to the other end of said torque bar,
said implement further comprising at least one main lift actuator coupled to said rear wheel support system in such a manner that actuation of said main lift actuator causes rotation of said torque bar and raising or lowering of said rear wheels relative to said main frame.

4. A tillage implement as claimed in claim 3 ,
wherein said mechanical linkage system comprises at least one extension arm coupled to and extending forwardly from said torque bar,
said mechanical linkage system comprising a rocker frame coupled to said rocker bar at said rocker pivot axis,
said mechanical linkage system comprising at least one rear transfer member coupled to and extending between said extension arm and said rocker frame in a manner such that movement of said extension arm causes movement of said rocker frame.

5. A tillage implement as claimed in claim 4 ,
wherein said mechanical linkage system comprises left and right actuator arms, left and right front transfer members, and left and right connection arms,
said left and right actuator arms being coupled to said rocker bar on opposite sides of said rocker pivot axis,
said left and right connection arms being coupled to said left and right front wheel support system respectively,
said left and right front transfer members being coupled between said left and right actuator arms and connection arms respectively.

6. A tillage implement as claimed in claim 1 ,
wherein said tillage implement is a field cultivator.

7. A tillage implement comprising:
a substantially rigid frame carrying a plurality of tillage tools for working the ground as the frame advances along a path of travel;
a pair of laterally spaced apart front wheels adjacent the front of the frame with respect to the direction of travel of the frame,
each of said front wheels being shiftably coupled with said frame for up and down movement relative to the frame;
a rear wheel assembly adjacent the rear of the frame with respect to the direction of travel of the frame,
said rear wheel assembly being shiftably coupled with said frame for up and down movement relative to the frame;
powered actuating mechanism operably coupled between said frame and said rear wheel assembly for raising and lowering said rear wheel assembly relative to the frame whereby to lift and lower the rear of said frame relative to the ground; and
a linkage system operably connecting said rear wheel assembly with said front wheels for transmitting up and down motion of said rear wheel assembly to said front wheels for causing the front of said frame to raise and lower simultaneously with the rear of said frame,
said linkage system including a front linkage extending rearwardly from said front wheels, a rear linkage extending forwardly from said rear wheel assembly, and a coupling interconnecting said front and rear linkages in a manner that permits said front wheels to shift upwardly or downwardly relative to one another in equal amounts and in opposite directions for maintaining the load of the front of the frame equalized on both of said front wheels as changes in terrain are encountered,
said coupling comprising a rocker bar pivotally attached to said rear linkage for rocking movement about a pivot axis located between opposite ends of said bar,
said front linkage comprising a pair of front links connected to respective ones of said front wheels and coupled with said rocker bar on opposite sides of said pivot axis,
said rear linkage including a rocker support frame at a forward end of the rear linkage,
said rocker support frame having a pivot connection with said rocker bar that defines said pivot axis of the rocker bar,
said pivot axis of the rocker bar being generally upright.

8. A tillage implement as claimed in claim 7 ,
said rocker support frame being swingably mounted on said frame of the implement for fore-and-aft movement of the rocker support frame and said rocker bar with said front and rear linkages during raising and lowering of said rear wheel assembly,
said rocker bar pivoting about said pivot axis relative to said rocker support frame during equal and opposite up and down shifting of said front wheels.

9. A tillage implement as claimed in claim 7 ,
a pair of front wheel support systems, each coupling a respective front wheel to said frame,
each of said front wheel support systems including a four-bar linkage connected to said frame of the implement for up and down swinging movement,
each of said front links being operably connected to a corresponding one of said four-bar linkages.

10. A tillage implement as claimed in claim 9 ,
each of said front wheels comprising a castor wheel.

11. A tillage implement as claimed in claim 7 ,
said rear wheel assembly including a transverse member pivotal about a transverse axis during raising and lowering of said rear wheel assembly and crank arm structure projecting laterally outwardly from said member,
said rear linkage being connected to an outer end of said crank arm structure such that said rear linkage shifts fore-and-aft during pivoting movement of said transverse member.

12. A tillage implement as claimed in claim 9 ,
said coupling including a pair of hydraulic cylinders connected between said rear wh

Assignees

• Great Plains Mfg Inc

Inventors

• Ohnsat Michael J

Classifications

• A01B63/22 Primary

  operated by hydraulic or pneumatic means · CPC title