GB2246498A - Preparing a seed bed - Google Patents

Abstract

An agricultural implement comprises an implement frame having front packer means 16, intermediate carriage wheels 26 and rearwardly mounted power cultivator means 18, drill means 22 and rear packer means 24. The frame is fully trailed from a tractor drawhook or clevis. Lowering the wheels 26 enables the entire implement to be fully trailed whereby transport is simplified. Raising the wheels 26 relative to the frame causes the overhung weight of the rearward part of the implement to act on the packer wheels to increase their packing action by a lever effect arising from the fixed height of the tractor clevis. The packer increases the effectiveness of the power cultivator. <IMAGE>

Description

AGRICULTURAL IMPLEMENTS AND METHOD OF OPERATING SAME This invention relates to agricultural implements and methods of operating same. More particularly, the invention relates to an agricultural implement for performing two or more ground treatment operations in a single pass, for example a combined cultivator and drill implement capable of transforming a ploughed field into a drilled seed bed in a single pass.

Prior proposals include various tillage implements with the combination of a packer and a cultivator. It is now well accepted that a packer operating in front of a cultivator, particularly a power cultivator, greatly increases the effectiveness of the cultivator.

Prior proposals relating to the combination of cultivating and drilling implements have mostly involved fully mounted implements. Such proposals may include semi-mounted implements in which the forward end of the implement is mounted on the height-adjustable draft links of the tractor, together with a power lifted and lowered rear castor wheel or wheels.

The shortcomings of these prior proposals includes the following. Firstly, fully mounted implements while meeting manoeuvrability requirements, suffer from excess overhung weight at the rear of the tractor, particularly if a packer is provided as well as a drill. This has led to the need to provide front weights on the tractor (which is a complication adding to the time taken to prepare the tractor/implement combination for work). The alternative to this is to mount the packer at the front of the tractor or even to mid-mount it. These latter proposals lead to problems associated with the need for a front linkage on the tractor, control of same, and the time taken to front or mid-mount the packer on the tractor.

In the case of prior proposals (if any) relating to semimounted implements having castor wheels at the rear, it is inherent in such a design that these castor wheels become unstable and dangerous at transport speeds for agricultural implements. It will be understood that there is a considerable need for an agricultural implement to have an ability to be road-transported at acceptable speeds so as to service widely spaced farming locations. It is a well known and observable fact that castor wheels tend to oscillate in use. While this is acceptable in relation to supermarket trolleys, it is clearly not so in relation to large agricultural implements carrying very substantial weight.A further factor in this regard is that the draft links on a tractor, which carry the front end of a semi-mounted implement are usually controlled by a single-acting ram or rams and therefore any lifting forces applied to the front of the implement will tend to lift it (because the tractor rams yield) and therefore such loads are not resisted by the tractor, and the tractor weight does not serve to assist penetration.

An object oL the present invention is to provide an agricultural implement and a method of using same offering the combination of simple connection to a tractor, simple transport arrangements, improved effectiveness of a packer or other ground treatment means on the implement, and reduced downward loading on the rear axle of the tractor; and/or improvements in relation to any one or more of the technical matters disclosed herein, or improvements generally.

According to the invention there is provided an agricultural implement and a method of operating same as defined in the accompanying claims.

In a preferred embodiment there is provided an agricultural implement for performing two or more ground treatment operations in a single pass including means to raise and lower a pair of ground wheels relative to a support frame.

The ground wheels are located at a position between two ground treatment means. In this way, on raising the ground wheels, not only is the implement lowered to the ground to commence work, but also the loading on the front ground treatment means is controllable. Thus, in the preferred embodiment, the implement frame is connected to a tractor in a fully trailed manner, so that the front end of the implement drawbar is at a fixed height relative to the tractor wheels. Thus, the front end of the implement is effectively at a fixed height and, if necessary, substantially the entire weight of the implement can rest on the front ground treatment means.Due to the fore/aft length of the implement frame there is, in addition, a moment or lever effect arising from the fixed pivotal connection of the drawbar to the tractor, whereby the weight of the implement at the rear end of the frame has an even greater effect than would be expected.

In the preferred embodiment, the forward ground treatment means comprising a packer, such as heavy tyred wheels or metallic packer rings, and the rearward ground treatment means comprises cultivator means, such as a power-driven rotary cultivator together with, if desired, a seed drill and associated rear packer means to consolidate the seed bed.

Also in the preferred embodiment, the height relative to the frame of the front ground treatment means, such as the packer means, can be adjusted so as to vary the mount of downward loading applied during use. Equally, for wet conditions, the height adjustable wheel means can be positioned during work so as themselves to carry at least some of the weight of the implement, thereby to reduce and perhaps minimise the downward loading applied to the front packer and/or the rear packer.

With regard to the location of the wheel means on the frame, this is chosen so as to conveniently raise the frame and the ground treatment means mounted on it for transport purposes. The exact location is not particularly critical.

If located at the region of the forward end of the implement then the upward loading on the drawbar during transport may be excessive. Equally, if located towards the rear end of the implement, drawbar loadings during transport will be downwards and there will be required an unduly large downward travel of the wheels to raise the frame for transport. Preferably, the wheels are located between the forward ground treatment means such as the packer, and the rearward ground treatment means.

In a preferred embodiment described below, the tractor has no need to carry extra weight and the tyres can be run at the lowest pressure recommended the tyre manufacture. The weight of the implement during work is shared by the flotation tyres on the implement, the front tyre packer, and the rear packing means, together with the power cultivator and the coulters. In addition, part of the weight of the tractor can be carried by the front tyre packing means to ensure even consolidation across the width of the drill. When the soil is dry, more pressure can be applied to the front and rear packing means so as to produce a maximum crushing of clods.

In wet conditions all the pressure on the packing means can be removed if necessary by appropriately loading the wheels of the implement. In addition, the loading of the front packing means can be simply adjusted by a pin system.

In the preferred embodiment the implement can be used as a cultivator in those parts of a field which require additional working.

In the preferred embodiment there is provided a method and apparatus for ground treatment with or without planting seeds. The apparatus comprises a frame and an associated axle which can be raised and lowered. The function of the axle is to carry and to raise and lower packing means ahead of itself, a seed tank ahead of and above itself, and a power cultivator plus drill coulters and an associated packer or press behind itself. The axle carries all of the weight of the implement during transport and raises and lowers it out of and into work, and yet the implement imposes no weight or even applies an upthrust to the tractor. The location of the front packing means is unique whereby high loadings can be imposed on it.

On the other hand, loading of the rear packer can be reduced by suitable actuation of the axle and wheel assembly of the frame so as to carry part of the loading that would otherwise be applied. High pressure loading of the packer ahead of the cultivator improves performance of the machine significantly and low to medium pressure on the packer behind the frill coulters is beneficial to seed germination by retaining moisture and reducing slug activity around the seed.

Additionally, herbicide perform on the seed bed is improved.

The arrangement allows a seed tank of large capacity to be positioned between the ground wheels and the tractor axle.

In this way, the weight of the tank is shared by both axles and excessive weight on the tractor wheels is avoided. The whole machine can be attached and detached from the tractor in less than 5 minutes due to the simple draw-bar attachment system. This compares very favourably with other implements which can take up to an hour to attach and detach.

As compared with fully mounted machines, the preferred embodiment spreads the weight of the implement over one more axle. This is of a particular significance for the large seed tank mounted between the tractor rear axle and the wheels of the implement. Thus the tractor rear axle carries less weight than normal, especially when compared with fully mounted machines where all the machine overhangs the tractor rear axle.

The carriage wheels on the implement include a positive mechanical depth control which is much more effective than using lift arms to control depth as is often the case with fully mounted machines. Likewise, the trailed combination can follow ground contours much better than the fully mounted machine which tends to pitch and toss on account of the rigid tractor top link.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which : Fig 1 shows, somewhat diagrammatically, a plan view of a tractor and combined seed drill and cultivator implement; and Fig 2 shows the tractor/implement combination in its road transport configuration, a perspective view from the rear and to one side; Fig 3 shows, in a view similar to that of Fig 2, the tractor and implement combination in its working configuration; Fig 4 shows a perspective view of the implement only, of the preceding figures, viewed from the front and to one side; and Fig 5 shows, purely diagrammatically, the principle upon which the implement applies extra weight to its front packer by virtue of a lever effect.

In the accompanying Figures, Figures 2, 3 and 4 are initially filed in the form of colour photographs. It is intended to file corresponding drawings showing the identical views, in formal form, within the time permitted.

As shown in the drawings, a combined drill and cultivator implement 10 to be drawn by a tractor 12 comprises a frame 14 carrying ground treatment means including an assembly of packer wheels 16, a power-driven cultivator 18, a seed drill including a seed hopper 20 and an array of coulters 22, and a rear spiral press or packer 24 to consolidate the seed bed.

In order to raise and lower frame 14 and the ground treatment apparatus mounted on it there are provided ground wheels, or carriage wheels 26 mounted on an axle 28. Axle 28 is mounted on frame 14 by hinge arms 30, and the axle is raised and lowered by hydraulic cylinders 32 which likewise act between the frame and the axle.

Also shown in Fig 1 are a levelling board 34 to level the seed bed immediately prior to entry of coulters 22 therein, and a frame 36 supporting rear packer 24 on the main implement frame 14.

Power cultivator 18 is driven by tractor 12 through power-take-off shafts 38. At 40 there is shown the location for additional weights or an additional front packer.

Implement 10 is connected to tractor 12 by a simple drawbar 42 connecting to the tractor's drawbar hitch point in the usual manner of a fully trailed implement. In use, the drawbar hitch point is at a relatively fixed height with respect to the tractor rear wheels 44 and the associated rear axle 46. Fig 1 also shows the tractor machine body 48 and its front axle 50.

In Figs 2 to 4, the following structures can be readily identified. These parts include a loading platform 52 and associated steps 54 for hopper 20, whereby the latter can be filled centrally. A driven metering mechanism 56 at the base of hopper 20 serving to deliver seed at a defined rate to a pneumatic seed delivery mechanism 58 having delivery tubes 60 connected between mechanism 58 and the individual coulters 22.

The seed delivery mechanism 58 and tubes 60 may be a proprietary product, for example of the kind currently available under the trade mark Accord.

Power driven cultivator 18 may likewise be a proprietary product, for example that sold under the trade mark Lely Roterra having power-driven vertically extending cultivator teeth - not seen in Figs 2 to 4.

Rear packer 24 is shown in Figs 2 to 4 as being of helical construction and may, for example, be of the kind currently sold under the trade mark Flexi-Coil. Means is provided to enable the rear packer to be height adjusted relative to its mounting.

Implement 10 has markers which operate in the usual way.

Fig 4 shows one of the markers in its raised position and Fig 3 shows a marker in use. The markers 62 may be employed to control operation of the seed delivery mechanism.

In use, implement 10 is transported in the configuration shown in Fig 2. This is achieved by actuating rams 32 to lower wheels 26 relative to frame 14 so that the entire implement is raised about the pivotal connection to tractor 12. The implement can then be rapidly road transported in a safe and convenient configuration with the markers raised.

Then, to bring the implement into work, cylinders 32 are allowed to retract and permit wheels 26 to be raised relative to the implement frame, whereby the implement is lowered to the ground and can commence work.

Packer wheels 16 are mounted relative to the frame at an adjustable height by means of pivot arms 64, one of which is seen in Fig 4. A mechanism for allowing a selected height of the packer wheels to be chosen is provided by means of a bolt and a range of alignable holes through which the bolt can be inserted in order to fix the pivot arms at a chosen attitude, and thus the packer wheels at a chosen height.

To maximise the load on the packer wheels, they are positioned at their lowest position relative to the frame, and the ground wheels 26 are fully raised, whereby a lever effect is exerted on the front packer in the manner indicated in Fig 5.

As shown in Fig 5 the frame 14 of implement 10 is pivoted at 70 to the relatively fixed tractor clevis. The weight of the implement frame can be resolved into a force W acting at its rear end 72. Likewise, the weights of the forward and remaining ground treatment apparatus can be resolved into weights T1 and T2 acting on frame 14 where indicated. These forces all produce a turning moment on frame 14 about pivot 70 in the clockwise direction as seen in Fig 5, whereby the loading on the packer wheels at 74 is amplified. This turning moment could be further increased by lifting wheels 26 from the ground. The turning force about pivot 70 is resisted by the weight of the tractor.

In the above embodiment, the carriage wheels or ground support wheels 26 of implement 10 are of course fixed in their fore/aft directional attitude and serve to permit steering of the fully trailed implement by the tractor in the same manner as the wheels on any normal trailed implement.

Interestingly, in the above embodiment there has been provided a combined drill and cultivator which is quick and easy to hitch to a tractor, which has a front packer which can be readily heavily loaded, the implement is manoeuvrable and readily handled for road transport in the manner of a trailed implement, produces effective tilth from the combination of the packer and a power driven cultivator, simultaneous drilling of seeds is performed together with consolidation of the seed bed, and all this without imposing excessive overhung weight on the tractor and its suspension.

In the above embodiments, trailing the implement allows it to follow ground contours far better than mounted combinations. Working depth of the whole implement is set by adjustable stops on the main implement's wheels. The two hydraulic rams raise and lower the implement into work by lifting and lowering the axle, but there is also separate depth or pressure control for each of the individual ground treatment means on the implement. For the seed drill coulters, the original Accord parallelogram coulter bar depth control has been retained, but positive stops and stronger springs have been added.

Claims (16)

CLAIMS :

1 An agricultural implement to perform two or more ground treatment operations in a single pass, the implement comprising a) a frame extending in the fore/aft direction; b) at least two ground treatment means carried on said frame; c) means to raise and lower the frame and said ground treatment means relative to the ground, between working and transport positions; and d) said means to raise and lower said frame and said ground treatment means comprises wheel means on said frame and which is height-adjustable; characterised by e) said wheels means is located to act on said frame so as to raise for transport both a forward one of said ground treatment means and another of said ground treatment means so that, in use, when said wheel means is raised to lower said frame, the overhung weight of said other of said ground treatment means acts to increase the loading on said forward one thereof.

2 An agricultural implement to perform two or more ground treatment operations in a single pass and having means to raise and lower ground wheels relative to a support frame so as to lower and raise two ground treatment means mounted on said frame.

3 An implement according to claim 1 or claim 2 characterised by said forward one of said ground treatment means comprises packer means and said other of said ground treatment means comprising cultivator means.

4 An implement according to any one of the preceding claims characterised by a drawbar at the forward end of said implement and adapted to be connected to fixed height trailing means on an agricultural tractor, for example a drawhook or clevis.

5 An implement according to any one of the preceding claims characterised by means to height-adjust said forward one of said ground treatment means relative to the frame.

6 An implement according to any one of the preceding claims characterised in that said other of said ground treatment means comprises power-driven cultivator means.

7 An implement according to any one of the preceding claims characterised in that said other ground treatment means comprises drill means and a hopper for supplying seed and/or fertiliser thereto.

8 An implement according to claim 7 characterised in that said other of said ground treatment means comprises rear packing means for said drill means.

9 An implement according to any one of the preceding claims characterised by said wheel means being positionable for work at one or more selectable heights whereby the wheel means can carry at least some of the weight of said implement during work.

10 An implement according to claim 9 characterised by means to vary the height of said wheel means so as to vary the proportion of the weight carried by said wheel means during work.

11 An agricultural implement to perform two or more ground treatment operations in a single pass, substantially as described herein with reference to the accompanying drawings.

12 A method of ground treatment comprising performing two or more ground treatment operations in a single pass of an agricultural implement, the method comprising : a) providing an agricultural implement comprising the features set forth in the pre-characterising portion of claim 1; characterised by b) locating said wheel means so as to act on said frame so as to raise for transport both a forward one and another one of said ground treatment means, and raising said wheel means relative to said frame so that, in use, the overhung weight of said other of said ground treatment means acts to increase the loading on said forward one of said ground treatment means.

13 A method of ground treatment comprising performing two or more ground treatment operations in a single pass of an agricultural implement, the method comprising raising ground wheels relative to a support frame so that the loading on a forward one of ground treatment means mounted on the frame is increased by the overhung weight of a rearwardly located ground treatment means also mounted on said frame.

14 A method according to claim 12 or claim 13 characterised by the step of height adjusting relative to said frame said forward ground treatment means.

15 A method according to any one of claims 12 to 14 characterised by the step of causing said wheel means to be height adjusted relative to said frame so as to vary the loading on said ground treatment means applied by the weight of the implement, in accordance with ground conditions.

16 A method of ground treatment substantially as described herein with reference to the accompanying drawings.