CA2550048C - Differential connecting rod and draft cable for agricultural tillage device - Google Patents

Abstract

The invention discloses a differential connecting rod and draft cable for an agricultural tillage device. The invention consists of a differential connecting rod which is positioned parallel to the center frame. The center frame is connected to the inner wing frame by a universal joint. The universal joint has a spherical bearing and a pivot. The pivot is positioned in a slot. The differential control rod positions the pivot in the slot. An 'L'-shaped linkage and a spring assembly pivotally support the rod. The draft cable is attached to the center frame hitch and outer wing. It is supported in the center by a folding support arm. This allows the wire to be moved when the cultivator is being transported. The draft cable transfers the draft force exerted on the outer wing to the center frame hitch.

Description

DIFFERENTIAL CONNECTING ROD AND
DRAFT CABLE FOR AGRICULTURAL TILLAGE DEVICE
This is a divisional of application serial number 2,287,627 filed October 26, 1999.
Field of the Invention This invention relates to the improvement of an agricultural ground-working cultivator.
More specifically it relates to an improvement of the centre frame of a cultivator and support for a pair of opposing wings on the said cultivator.

Background of the Invention The need to till and cultivate soil for the planting of crops has been accomplished since the earliest days of civilisation. More recently, tillage devices have increased in complexity and size, depending on the type of crops, quantity and soil being tilled. There has also been an increased emphasis on conserving natural resources resulting in these concerns being integrated in modern tillage systems. These concerns have resulted in larger and more complex tillage systems that assist in achieving these goals.
A larger tillage system allows a single operator to perform tillage operations on a greater area.
More sophisticated tillage systems further allow for the accomplishment of low till and no till farming techniques. Low till and no till farming encourages tilling, planting and fertilising in a single pass of the tillage device or cultivator through the field. By only disturbing the soil a single time, there is less soil compaction, less moisture loss, less pesticides and herbicides needed and less fertiliser required. However, these larger and more complex tillage systems create complexities that were previously unknown in the art.

Previously, an agricultural tractor could pull a relatively small tillage device or cultivator.
As the tillage device or cultivator moved over hills and similar undulations in the terrain all the ground-working implements maintained contact with the soil. The width of the tillage device was sufficiently small for it generally not to have problems maintaining ground contact. However, as the tillage devices were increased in width, so as to be able to till a greater area in a single pass, the undulations in the ground resulted in the ground-working tools failing always to contact the earth.

Furthermore, to transport the tillage device or cultivator for the farming operations it was necessary for the device to be capable of being collapsed to a width sufficient to be moved. To accomplish these goals, a centre section with a set of pivotable wings was designed. The wings could pivot horizontally relative to the centre section allowing the tillage device to accommodate some undulations in the ground. The wings could also be folded into the centre section allowing for easy transport before and after farming operations. Eventually, an outer set of wings was added increasing the width of the tillage device.

Figure 1 illustrates the general configuration of a tillage device or cultivator. Specifically, there is a centre section directly behind the tractor. There is a set of inner wings and outer wings respectively surrounding the centre section. Some cultivators are folded into the transport position along an axis along the direction of travel; other cultivators are folded along a diagonal axis.

In prior art cultivators, the wings can rotate on an axis in the direction of travel, the wings generally cannot rotate, flex or bend on an axis perpendicular to travel.
Finally, the additional inner wings and outer wings create large additional draft forces on the frame of the cultivator, draft forces being those created when the ground-working tool is pulled through the soil.

These are complex problems to overcome, especially when considering the need for the tillage device to be a collapsed from its field operation mode to the compact transportation mode.

Consequently, the need exists for a linkage, which allows for the inner wings to move transversely to the centre section of a tillage device. The need also exists for a means to help distribute the draft load generated by the outer wings.

Summary of the Invention The present invention relates generally to agricultural cultivators having a central section flanked by wings which are pivotally connected to the centre section in such a manner that in addition to being able to pivot relative the centre section about an axis parallel to the direction of travel of the cultivator the wings may pivot relative to the centre section about a horizontal axis transverse to the direction of travel of the cultivator and about a vertical axis.

In a preferred embodiment of the invention a draft support wire acts as a means by which the draft force on the outer wings is transferred to the centre hitch frame.
The wire is pivotally attached to the outer wing and wing hitch frame. Supporting the wire is a folding support arm. The arm has an outer arm pivotally attached to an inner arm. The inner arm is attached to the wing hitch frame. Controlling the outer arm is a chain that is attached to the wing hitch frame by a chain arm. The chain is also attached to an elongated plate on the outer arm. This design allows the support arm to be folded when the cultivator is in the transportation mode.

Also, in a preferred embodiment of the present invention, the centre section is attached to the wings by a modified universal joint that is attached to the centre frame by a spherical bearing and pivot allowing for three axes of movement. The pivot is positioned inside a slot on a bracket. An L-shaped linkage controls the movement of the pivot within the slot.
The linkage is pivotally attached to the centre frame and a differential connecting rod. A
spring assembly supports the centre of the differential connecting rod and biases the pivot in the slot to a centre position.

The disclosure also describes connecting rods and draft cables as hereinafter set forth.
Brief Description of the Drawings The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is an overhead schematic view of an agricultural cultivator, Figure 2 is a side, overhead view of the differential connecting rod in the field mode, Figure 3 is a side, overhead view of the differential connecting rod in the transport mode, Figure 4A is a side view of the cultivator in the headland mode, Figure 4B is a rear view of the cultivator in the field mode, Figure 4C is a rear view of the cultivator in the transportation mode, Figure 4D is a side, front view of the transport assembly, Figure 4E is a side, front view of the differential rod while the cultivator is in field operating mode, Figure 4F is a view of the folding support wire when the cultivator is in the transportation mode, Figure 5 is a front view of the differential connecting rod, showing both spring assemblies, and Figure 6 is a front view of the left side of the differential connecting rod showing a single spring assembly.

Detailed Description of the Preferred Embodiments Referring to the drawings, it is possible to observe the major elements and general operation of the present invention. The terms "left" and "right" are used as a matter of convenience and are determined by standing at the rear of the tillage device or cultivator and facing the forward end in the normal direction of travel when the tillage device or cultivator is operating in the field (field mode, see figure 4B). Likewise, forward and rearward are determined by normal direction of travel in the field mode of the tillage device or cultivator. Upward or downward orientations are relative to the ground or operating surface. Horizontal or vertical planes are also relative to ground.

Figure 1 illustrates a general overhead view of a pull-type tillage device or cultivator. A
conventional tillage device or cultivator consists of a centre section 2 with two inner wings 3 positioned next to the centre section 2. Next to the inner wings 3 are two outer wings 4. The tillage device or cultivator 1 has a triangular shaped centre frame hitch 9.
The base of this hitch 9 is attached to the centre section 2 and the front of the hitch 9 is attached to a tractor mount 8. The tractor mount 8 is attached to a conventional agricultural tractor. The tractor pulls the tillage device or cultivator 2 and also supplies hydraulic power or mechanical power via the power-take-off (PTO) to the various implements on the cultivator 2.

Supplementing the centre frame hitch 9 is the wing hitch frame 10 that provides draft support to the inner wings 3. Supporting the entire cultivator 2 are a series of castor wheels 5 located towards the front of the cultivator 2 and a series of packing or rear supporting wheels 7 located towards the rear of the cultivator 2.

The centre section 2 has a centre frame 22 and a toolbar 6 which supports various ground-working implements. Such implements are well known in the art and include ploughs, coulters, discs as well as other implements. Each inner wing 3 and outer wing 4 also possesses a tool bar 6. The inner wing 3 also has an inner wing frame 13. The centre frame 22 and inner wing frame 13 are connected by means of a universal joint assembly 21 that can best be seen in figures 2 and 3.

Figure 1 shows the cultivator 2 in the field mode. In the field mode, the inner and outer wings 3 and 4 are fully extended horizontally across the field. There is also a headland mode (see figure 4A) where the wings (2 and 3) are still extended, but the tool bars 6 are raised out of the soil. The headland mode is used at the end of a crop row when an operator wishes to tum the tractor and cultivator 2 around and partially raise the ground working implements. The transportation mode (see figure 4C) involves rotating the centre frame 22 and inner wing frame 13 upwards through 90 This raises the toolbars 6 and packing wheels 6 up into the air. The wings 3 and 4 are then rotated rearwards. This results in a cultivator that is narrow and may be transported to another field.

The draft support wire 50 can best be seen in figure 1 and extends from the wing hitch frame 10 to the outer wing 4. During field operations, this wire can transfer some of the draft force in the outer wing 4 to the centre hitch frame 9.

As seen in figures 2 and 3, the differential connecting rod 20 is located parallel to the centre frame 22. It controls the movement of the universal joint assembly 21.
There are two, identical connecting rods 20 which control respective universal joint assemblies 21 located on the left and right sides of the centre frame 22. For purposes of brevity, only the right side is illustrated and discussed. However, the left side works in an analogous fashion.

The universal joint assembly consists of a universal joint 25 with a centre frame attach 27 and a wing attach 26. Generally speaking, the centre frame 22 is connected to the centre frame attach 27 and the wing frame is connected to the wing attach 26. Figure 2 shows the centre frame 22 and universal joint assembly 21 oriented in the field mode. Figure 3 illustrates the centre frame 22 and universal joint assembly 21 rotated forward 90 into the transportation mode.

Connecting the universal joint assembly 21 to the centre frame 22 is bracket 23 with a slot 24. At the other end of the universal joint 25 there is a conventional spherical bearing 28 which allows for a full range of motion and permits the universal joint 25 to move in the slot 24. This allows the wing section a full range of motion about the universal joint.

In the prior art, the wing section could only rotate about an axis parallel to the direction of travel. By contrast, in the present invention, the wing section can rotate upwards or downwards on an axis perpendicular to the direction of travel and about a vertical axis.
However, to control the movement of the universal joint 25 within the slot 24, there is the differential connecting rod 20.

The universal joint assembly 21 has three axes of motion. The three-axes joint consists of a universal joint with one joint pin connected to a yoke on the centre frame 22 at bearing 28 at one end and constrained in the slot 24 at the other end, defining a first axis longitudinal to the pin and a second axis perpendicular to the pin through the bearing 28.
The pin 28 is allowed freedom to rotate about the second axis within the limits of the slot 24 of the bracket 23. The second axis is therefor generally transverse. A
third axis is defined by the joint pin connected to a yoke on the wing frame, which is perpendicular to the first axis and is a pivot for inner wings 3 to follow ground elevations when in transport.

The first axis in the transport position allows rear folding of the wing frames and in the field position is a pivot allowing wings to follow ground elevations as shown in figure 2.
The first axis allows rear folding of the wing frames. The second axis allows the drawbar to rotate relative to the centre section so that the attached gangs are on average, aligned with the pitch of the ground (rising or falling slope in the direction of travel). The range of the second axis rotation is limited by the ends of the slot 24.

In figure 2, the differential connecting rod 20 is attached towards the centre of the centre frame 22 by means of the spring assembly 40. The spring assembly 40 will be described in greater detail below. At the end of the centre frame 22, the connecting rod is pivotally attached to an 'L'-shaped linkage 30. The 'L'-shaped linkage is pivotally attached to the centre frame 22 at the linkage pivot 31. The end of the 'L'-shaped linkage 30 is attached to the universal joint assembly 21 at the pivot 29.

Turning to figures 5 and 6, it is possible to observe both spring assemblies 40. As previously indicated both spring assemblies 40 are identical in construction and operation.
Figure 6 illustrates a single spring assembly 40 viewed overhead. Each spring assembly 40 consists of a co-axial spring 41 held in a slightly compressed positioned by a pair of threaded tie rods 42. The differential connecting rod 20 is in two parts that, in field operation abut each other at the centre of the centre frame section. Each part of the connecting rod 20 is slidably supported by a inner stop block 46 which is attached to the frame 22. The differential connecting rod 20 is biased to a central position as shown by the spring assembly 40.

The spring assembly 40 is attached at one end to the inner stop block 46 by tie rods 42.
The spring is co-axial with the differential connecting rod 20. It is constrained between two abutment inner sliding blocks 44a and 44b. Inner sliding block 44a is constrained by nuts 45 at the end of tie rods 42. A pair of outer sliding blocks 43a are attached to the differential connecting rod 20 (secured by bolt shown) and are in abutment with an inner sliding block 44a. Another pair of outer sliding blocks 43b are welded to the differential tie rod 20 and are in abutment with inner sliding block 44b, passing through the inner stop block 46.

In operation, when a wing rotates about the second axis in direction 66a, driven to an average position between the attached gangs as the ground slope varies, then it drives the L-shape lever and then the connecting rod 20 in direction 66. The spring is compressed between the outer sliding blocks 43a and the inner stop block 46, between which are also pressed inner sliding block 44a and 44b. The motion is directed onto the other abutting connecting rod and causes the opposite wing to rotate about its second axis in an equal amount in the opposite direction. Therefor the centre section is suspended at an average height between the two adjacent wing sections.

When being driven from the other wing section, the connecting rod 20 is forced in the other direction 67. Outer sliding blocks 44b abut onto the inner sliding block 43b. The spring shown in figure 6 is then compressed between the outer sliding blocks 43b and nuts 45, between which again pressed the inner sliding blocks 44b and 44a are again pressed. The spring works in both directions to bias the half of the connecting rod assembly to a central position. The other half works the same way. The height of centre section is driven by the three axes joints attaching the wing frames on either side. The differential connecting rod assembly keeps it at an average position between the two wing frames and biases the wing frames into rotational alignment with the centre frame about the second axis. It also distributes weight transfer force that may be optionally applied to the centre frame onto each of the wing frames. It should be noted that there are several possible secondary embodiments involving the connecting rods.

When the cultivator 2 is in the transportation mode, as seen in figure 3, it is important the pivot 29 be fixed in the slot 24. Because the wing section's weight is supported partially by the universal assembly 21, it is important that the pivot 29 should not impact the slot 24. To achieve that goal, a transport assembly 47 has been included to prevent translation of the differential rod. The transport assembly 47 has a tongue 48 attached to the centre frame 22. A tongue spring 49 is biased between the differential connecting rods 20 as seen in figure 3. During the transition from the field mode (as seen in figure 2) to the transportation mode (as seen in figure 3), the wings are folded upwards 90 and the ends of the wings are folded rearwards. This places a force similar to 67a on the pivot 29.
These forces pull both differential connecting rods 20 away from the centre of the centre frame 22. The spring-biased tongue 49 is inserted between the rods when the centre frame 22 is rotated forward 90 . This locks the rods and holds the pivot 29 at one end of the slot 24 during transport (as seen in figure 4D). Conversely, the tongue 48 is removed from the between the rods when the centre frame 22 is rotated into the field position.

The folding draft support wire 50 can be seen in figures 1 and 4F. The wire 50 is attached to the cultivator 2 at three points. The wire 50 is pivotally attached to the inner hitch 52.
At the opposite end, the wire 50 is pivotally attached to the outer wing hitch 51 (see figure 4F). Supporting the wire 50 in the middle is the folding support arm 53. The support arm 53 is such that in the operating position the wire 50 does not form a straight line between the points of connection with the inner and outer hitches 51 and 52, i.e. as shown in Fig. 1 the wire has a shallow V-shape configuration. The folding draft support wire 50 is designed to transfer the draft force created by the outer wings to the centre hitch frame. Failure to transfer the draft force could result in the outer wings twisting behind the centre section. As seen in figure 4F, the support wire 50 is lifted towards the centre frame and wing sections during the transportation mode. The folding support arm 53 accomplishes this. The folding support arm 53 consists of an inner arm 54 attached to the wing hitch frame 10. A hinge 56 pivotally attaches the outer arm 55. To ensure that the support arm 53 remains fully extended during the field mode, the outer arm 55 has an elongated plate 55a. Attached to the elongated plate 55a is a chain 57. The chain is connected to the wing hitch frame 10 by a pivotally mounted chain arm 58. The support wire 50 is attached to the top of the outer arm 55.

During the field mode, the wing hitch frame 10 is rotated 90 downwards. The chain arm 58 pulls the elongated plate 55a and outer arm 55 away and downwards. This extends the draft wire 50. Conversely, when converting the cultivator from the field mode to the transport mode, the wing hitch frame 10 rotates upwards 90 . This allows the outer arm to pivot about the hinge 56. The wire is moved towards the hitch frame as seen in figure 4F.
It is the tension in the wire as the wing frames are folded rearwardly that causes the wire to be pulled in close to the frame in the transport position. The outer arm 55 guides the position of the wire up and over the wheel 5 so that it does not rub on the wheel or the ground in transport.

Claims (18)

Claims

1. A draft assembly for connecting a wing hitch frame to an outer wing of a cultivator capable of operating in a field mode and a transport mode and comprising:
a. a draft support wire;
b. an outer wing hitch attachable to the outer wing, said wire pivotally attachable to the outer wing hitch;
c. an inner hitch attachable to the wing hitch frame, said wire pivotally attachable to the inner hitch; and d. a folding support arm attachable to the wing hitch frame, said wire affixable to the support arm and said support arm being constructed and arranged to hold the wire in a fully extended position during operation in the field mode.

2. A draft assembly as claimed in claim 2, wherein said folding support arm further comprises:
a. an inner arm attachable to the wing hitch frame;
b. an outer arm pivotally connectable to the inner arm by a hinge;
c. a chain arm pivotally connectable to the wing hitch frame; and d. a chain for connecting the chain arm and the outer arm.

3. A pull-type agricultural tillage device operable in a field mode and a transport mode and having a wing hitch frame, an outer wing, and a draft assembly connecting the wing hitch frame to the outer wing, said draft assembly comprising:
a. a draft support wire;
b. an outer wing hitch attached to the outer wing, said wire pivotally attached to the outer wing hitch;
c. an inner hitch attached to the wing hitch frame, said wire pivotally attached to the inner hitch; and d. a folding support arm attached to the wing hitch frame, said wire affixed to the arm, whereby the outer wing is provided draft support during operation of the tillage device said support arm being constructed and arranged so as to be fully extended together with the draft wire during operation in the field mode, and to guide said wire upwardly into a transport mode position free of the ground and other components of the tillage device.

4. The tillage device of claim 3, wherein said folding support arm further comprises:
a. an inner arm attached to the wing hitch frame;
b. an outer arm pivotally connected to the inner arm by a hinge; said outer arm having an elongated plate;
c. a chain arm pivotally connected to the wing hitch frame; and d. a chain connecting the chain arm and the elongated plate, whereby the movement of the outer arm and inner arm is controlled.

5. The tillage device of claim 4, wherein there are only two draft cables positioned on each side of the pull-type tillage device.

6. The tillage device of claim 4, wherein the elongated plate secures the outer arm to the inner arm in an extended manner.

7. An agricultural implement having support wheels and adapted to be pulled by a tractor, said implement comprising:
a central frame with a front end and opposing sides and having a hitch frame affixed at said front end to said central frame adjacent said front end thereof and extending away therefrom in a first direction and terminating at the other end with a hitch for attachment to said tractor;
a pair of substantially identical, but reversed, wing frames with front ends, one connected to each side of said central frame at the front ends thereof, the connections between said wing frames and said central frame permitting said wing frames to be selectively moved from an operating position to a transport position by rotating about said front ends thereof 90° in said first direction and 90° in a second direction transverse to said first direction toward the respective side of said central frame, each side of said central frame including:
a draft support wire connected at one end to said hitch frame and connected at the other end to said wing frame at the front end thereof;
a support arm pivotally attached at one end to said wing frame at a position closer to said central frame than the position of connection of said support wire to said wing frame and attached to said support wire along the length thereof at the other end, the length of said support arm being such that in said operating position said support wire extends between the points of connection with said frames in a V-shape configuration as seen from above whereby to effect transfer of draft forces from the wing frame to the hitch frame;

said support arm and wire pivotable between said operating position where said support wire is taut and transfers draft forces between said wing frame and said hitch frame, and said transport position where said support wire is not taut and is held in position away from components operable in the transport position.

8. The implement of claim 7, further including:
a mechanical mechanism for pivoting said support arm between said operating and transport positions;
said mechanism interconnecting said support arm and said wing frame such that movement of said wing from into said transport position causes said mechanism to pivot said support arm into said transport position and movement of said wing frame into said operating position causes said mechanism to pivot said support arm into said operating position.

9. The implement of claim 8, wherein: said mechanism is a chain connected on one end to an elongate control arm affixed to said wing frame and on the other end to said support arm.

10. The implement of claim 9, wherein: said support arm is connected to said wing frame by a hinge.

11. The implement of claim 10, further including: an elongated plate affixed to said pivot arm and said chain is connected thereto.

12. An agricultural implement having support wheels and adapted to be pulled by a tractor, said implement comprising:
a central frame with a front end and opposing sides and having a central hitch frame affixed at said front end to said central frame adjacent said front end thereof and extending away therefrom in a first direction and terminating at the other end with a hitch for attachment to said tractor;

a pair of substantially identical, but reversed, inner wing frames with front ends, one connected to each side of said central frame at the front ends thereof;
a pair of substantially identical, but reversed, outer wing frames with front ends, one connected to each side of respective inner wing frames at the front ends thereof;
the connections between said inner wing frames and said central frame permitting said inner wing frames to be selectively moved from an operating position to a transport position by rotating about said front ends thereof 90° in said first direction and 90° in a second direction transverse to said first direction toward the respective side of said central frame;

said outer wing frames rotating with the respective inner wing frames when moving from said operating position to said transport position, each side of said central frame including:
a draft support wire connected at one end to said central hitch frame and connected at the other end to said outer wing frame at the front end thereof;
a support arm pivotally attached at one end to said inner wing frame at the front end thereof and attached to said support wire along the length thereof at the other end, the length of said support arm being such that in said operating position said support wire extends between the points of connection with said central hitch frame and said outer wing frame in a V-shape configuration as seen from above whereby to effect transfer of draft forces from the wing frame to the hitch frame;
said support arm and wire pivotable between said operating position where said support wire is taut and transfers draft forces between said outer wing frame and said central hitch frame, and said transport position where said support wire is not taut and is held in position away from components operable in the transport position.

13. The implement of claim 12, further including, on each side of said central frame:
a wing hitch frame interconnecting said central hitch frame and said front end of said inner wing frame.

14. The implement of claim 13, wherein:
said one end of said draft support wire is attached to said wing hitch frame.

15. The implement of claim 14, further including:
a mechanical mechanism for pivoting said support arm between said operating and transport positions;
said mechanism interconnecting said support arm and said inner wing frame such that movement of said inner wing into said transport position causes said mechanism to pivot said support arm into said transport position and movement of said inner wing frame into said operating position causes said mechanism to pivot said support arm into said operating position.

16. The implement of claim 15, wherein:
said mechanism is a chain connected on one end to an elongate control arm affixed to said inner wing frame and on the other end to said support arm.

17. The implement of claim 16, wherein:
said support arm is connected to said inner wing frame by a hinge.

18. The implement of claim 17, further including:
an elongated plate affixed to said pivot arm and said chain is connected thereto.