GB2088683A - Soil cultivating implements - Google Patents

Abstract

A soil cultivating implement comprises a row of power-driven rotary soil working members 3 and a shield plate 9 arranged adjacent to each end of the row, the plate being upwardly and downwardly adjustable in position relative to a corresponding carrier 11 to match the pre-selected working depth of the members 3. The shield plates 9 co-operates with the adjacent members 3 in crumbling and distributing soil and, in order to minimise the effect of a stone or other hard object becoming momentarily trapped between one of the plates 9 and an adjacent tine 4, the carrier 11 of each shield plate 9 is movable outwardly and upwardly along a guide slot 14 against the action of a restoring spring 17 in such a way that displacement of each shield plate 9 can take place without significant tilting. If the upper and outer ends of the guide slots 14 are reached by pivot pins 13 that are slidable therealong, said shield plates 9 and carriers 11 can turn further outwardly about the axes of the pivot pins 13. An alternative embodiment is described and illustrated in which the guide slots 14 are replaced by sleeve-formation slideways movable axially along oblique guide rods against the action of restoring springs. <IMAGE>

Description

SPECIFICATION Soil cultivating implements This invention relates to soil cultivating implements or machines of the kind which comprise an elongate frame portion that extends substantially horizontally perpendicular, or at least transverse, to the intended direction of operative travel of the implement or machine, said frame portion supporting a plurality of soil working members arranged in relatively neighbouring relationship and so as to be rotatable about upwardly extending (non-horizontal) axes, at least one end region of said frame portion having an upright shield plate connected to it so as to be capable of soilcrumbling and distributing co-operation with an adjacent soil working member during operation of the implement or machine, the or each shield plate being upwardly movable relative to said frame portion when the implement or machine is in operation.The expression "implement(s) or machine(s)" will be shortened to "implement(s)" alone throughout the remainder of this document for the sake of brevity.

Known implements of the kind set forth above generally produce very satisfactory results but it has been found that, when they are employed upon land having well above the average content of hard objects, such as stones and/or old roots and so on, the crumbling and distributing action which takes place between the shield plates and the rotary soil working members at the opposite ends of the elongate frame portion is disturbed to such an extent as considerably to reduce the cultivating efficiency of the implement in these regions.

The present invention seeks to overcome, or at least very significantly to reduce, the disadvantage of known implements which is mentioned above and the invention accordingly provides a soil cultivating implement of the kind set forth, wherein the or each shield plate is connected to said frame portion in such a way as to allow it to be movable upwardly and outwardly away from the centre of the frame portion without significant tilting.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a plan view of a soil cultivating implement in accordance with the invention shown connected to the rear of an agricultural tractor, Figure 2 is a rear elevation, to an enlarged scale, showing the parts at one side or end of the implement of Fig. 1 in greater detail, Figure 3 is a side elevation as seen in the direction indicated by an arrow Ill in Fig. 2, Figure 4 is a view to the same scale and from the same standpoint as Fig. 2 but illustrates a second embodiment constructed in accordance with the invention, and Figure 5 is a side elevation as seen in the direction indicated by an arrow V in Fig. 4.

Referring to the accompanying drawings, and firstly to Figs. 1 to 3 inclusive, the soil cultivating implement that is illustrated therein is in the nature of a power-driven rotary harrow and comprises a hollow box-section frame portion 1 that is of elongate formation extending substantially horizontally transverse and usually, as illustrated, substantially horizontally perpendicular, to the intended direction of operative travel of the implement that is indicated in Fig. 1 by an arrow A. A plurality, of which there are twelve in the example that is being described, of rotary soil working members 3 (Fig. 2) are arranged beneath the frame portion 1 in a single row that extends parallel to the transverse length of that frame portion.Each rotary soil working member 3 is formly but releasably secured to the lowermost end of a corresponding upwardly extending, and usually substantially vertically disposed, shaft 2 and it will be noted that the longitudinal axes of the shafts 2, which embody the axes of rotation of the soil working members 3, are spaced apart from one another by regular distances of substantially 25 centimetres so that, with tweleve of the soil working members 3 in the example that is being described, the implement has a working width of approximately, Ibut not necessarily exactly, 3 metres.Each rotary soil working member 3 comprises a diametrically opposed pair of cultivating members in the form of rigid soil working tines 4 with the downwardly projecting soil working portion of each tine 4 preferably swept back from top to bottom by a few degrees relative to the intended direction of operative rotation of the member 3 concerned, these directions of operative rotation being indicated by small arrows for two of the members 3 in Fig. 1 of the drawings. The distance between the lowermost ends of the two tines 4 of each pair is greater than the distance between the axes of rotation of neighbouring shafts 2 so that, during operation, the strips of soil which are worked by the individual members 3 overlap one another to form a single broad strip of worked ground.As will be evident from Fig. 2 of the drawings, neighbouring soil working members 3 along the single row thereof are so mounted on the downwardly projecting ends of the corresponding shafts 2 that they will not foul one another during rotation about the axes of those shafts 2.

The opposite ends of the hollow box-section frame portion 1 are closed by corresponding substantially vertical, or at least upright, side plates 5 which side plates 5 will usually, as illustrated, be parallel to one another and parallel or substantially parallel to the direc tion A (Fig. 1). The leading ends of the side plates 5, with respect to the direction A, are provided with substantially horizontally aligned pivot bolts 6 about which corresponding arms 7 can be turned upwardly and downwardly alongside the respective plates 5.

The arms 7 extend generally rearwardly with respect to the direction A from the pivot bolts 6 and have obiiquely downwardly and rearwardly projecting rearmost ends. The rear edge of each side plate 5, with respect to the direction A, has a greater vertical extent than does the leading edge thereof and said plate is formed, close to that rear edge, with a row of holes that are equidistant from the axis defined by the aligned pivot bolts 6.Each arm 7 is formed with at least one hole at the same distance from said axis and horizontal bolts are provided for entry through the hole, or at least one of the holes, in each arm 7 and through a chosen one of the row of holes in the adjoining side plate 5 so that, when the retaining bolts are installed and tightened, the arms 7 will be firmly but releasably positioned in corresponding angular settings about the axis defined by the pivot bolts 6. The extreme rearmost ends of the arms 7 carry horizontal bearings between which a ground roller 8 is mounted so as to be freely rotatable in those bearings about its own longitudinal axis. The ground roller 8 is an open-work roller of skeletal formation comprising an axially extending central member to which a plurality, such as five, of parallel support plates are perpendicularly secured at regularly spaced apart intervals.The circular support plates are formed at regularly spaced apart intervals around their edges with holes which receive a plurality of elongate elements in the form of rods or tubes. Two such elements are partially illustrated in Fig. 1 of the drawings from which it will be apparent that the elements are preferably arranged helically around the axis of rotation of the roller 8 so as skeletally to provide its circular cylindrical ground-contacting surface.

The opposite ends of the hollow frame portion 1 are provided, alongside the opposite ends of the single row of rotary soil working members 3, with corresponding shield plates 9, those plates 9 normally being disposed as shown in Figs. 1 to 3 of the drawings. The shield plates 9 co-operate with the neighbouring soil working members 3 at the opposite ends of the single row thereof in performing a crumbling and distributing action upon the worked soil in a manner generally analogous to the soil working action between neighbouring members 3 at locations spaced from the opposite ends of the single row thereof.In addition, the shield plates 9 prevent the rapidly moving tines 4 of the members 3 from flinging stones and other hard objects laterally of the path of travel of the soil cultivating implement so that the danger of damage to property and of injury to persons and livestock from this cause is very greatly reduced. Each shield plate 9 has a somewhat greater vertical extent at the front thereof, with respect to the direction A, than at its rear (see Fig. 3). The front and rear edges of the plates 9 are inclined upwardly and forwardly from the corresponding substantially horizontal lower edges with respect to the direction A and are parallel or substantially parallel to one another (see Fig. 2). Each shield plate 9 is adjustably secured to a corresponding carrier 11 by way of a pair of retaining bolts 10.To this end, each shield plate 9 is formed with two substantially vertical rows of holes at locations towards its front and rear edges; similarly, each carrier 11 is formed with at least two holes that can register with chosen holes in the rows thereof that are formed in the corresponding shield plate 9. Upon choosing appropriate holes, entering the retaining bolts 10 therethrough and tightening the latter, the shield plates 9 will be firmly but adjustably secured in chosen positions of adjustment relative to the carriers 11. This adjustment is performed having regard to the chosen working depth of the tines 4 of the soil working members 3 with a view to the lowermost substantially horizontal edges of the shield plates 9 being as close to ground level as possible whatever working depth of the tines 4 is selected.

The upper shaped edge of each carrier 11 is provided, at substantially the front and rear thereof with respect to the direction A, with two support strips 1 2 whose general planes are parallel to each other and perpendicular or substantially perpendicular to the direction A.

Moreover, a plane which contains the axis of rotation of each shaft 2 in the single row thereof is parallel to the general planes of the two support strips 1 2 that lie adjacent to each end of the frame portion 1. Fig. 2 of the drawings shows that each support strip 12 is inclined outwardly, and upwardly at a few degrees to the vertical, from the lowermost end thereof which is secured to the respective carrier 11. The tops of the two support strips 12 which correspond to each carrier 11 carry corresponding substantially horizontal pivot pins 1 3 which pivot pins are aligned in a direction that is parallel or substantially parallel to the direction A. Each pivot pin 1 3 is entered through a slot 14 which, as can be seen in Fig. 2, extends upwardly and outwardly with respect to the centre of the implement at an angle of, for example, 30 to the underlying ground surface. Each slot 14 is formed in the upper and outer end of a corresponding substantially planar bracket 1 5 whose lower and inner end is bent over through 90 to be firmly but releasably fastened to the top of the hollow frame portion 1. Once again, the general planes of the brackets 1 5 are parallel or substantially paral lel to a plane which contains the axes of rotation (longitudinal axes) of the single row of shafts 2.The two brackets 1 5 at each end of the hollow frame portion 1 are strengtheningly interconnected by a corresponding tie 1 6 which extends substantially horizontally parallel to the direction A. A tension spring 1 7 is stretched between an anchorage on each bracket 1 5 and an achorage lug bent over from each support strip 12, the springs 1 7 being located alongside upper regions of the brackets 1 5 at locations spaced by short distances from the axes defined by the corresponding pivot pins 1 3. The two tension springs 1 7 of each pair thus tend to maintain the corresponding pivot pins 1 3 at the inner and lower ends of the associated slots 1 4 and to turn the shield plates 9 inwardly about the axes defined by the pivot pins 1 3 until the carriers 11 bear against the rubber or other resilient stops 5A mounted on the outer surfaces of the frame portion side plates 5.In this connection, it will be realised from Fig. 1 of the drawings that the parts which have just been described at one end of the hollow frame portion 1 are symmetrically duplicated at the opposite end thereof.

Each shaft 2 carries, inside the hollow frame portion 1, a corresponding straighttoothed or spur-toothed pinion 1 8 and the twelve pinions 1 8 are of such sizes that the teeth of each of them are in mesh with those of the or each neighbouring pinion 1 8 along the row or train of twelve such pinions. Thus, each pinion 18, shaft 2 and soil working members 3 will revolve, during operation, in the opposite direction to the or each immediately neighbouring similar assembly.However, the shaft 2 which corresponds to one of the centre pair of soil working members 3 along the row of twelve thereof has an upward extension through a top cover plate of the hollow frame portion 1 into a gear box 1 9. The shaft extension is in driven connection, inside the gear box 19, by way of bevel pinions that are not visible in the drawings with a horizontal shaft that extends substantially parallel to the direction A.This horizontal shaft (not visible) is in driven connection, in turn, with a further parallel horizontal shaft by way of a change-speed gear 20 located at the rear of the gear box 19, the leading end of this second substantially horizontal shaft projecting forwardly from the front of the gear box 1 9 in the direction A where it serves as a rotary input shaft 21 to be placed in driven connection with the rear power take-off shaft of an agricultural tractor or other operating vehicle through the intermediary of a telescopic transmission shaft 22, which is of a construction that is known per se, having universal joints at its opposite ends.It is not necessary to describe the change-speed gear 20 in detail for the purposes of the present invention and it suffices to say that pairs of toothed pinions giving different transmission ratios can be selectively mounted on the splinted ends of the two parallel substantially horizontal shafts that project into that changespeed gear from the gear box 1 9 as a result of which the tweleve soil working members 3 can be rotated at faster or slower speeds, having regard to the nature and condition of the soil that is to be worked and the working depth that is chosen, without having to alter the initiating speed of rotation of the power take-off shaft at the rear of the agricultural tractor or other operating and propelling vehicle.The front of the hollow frame portion 1, with respect to the direction A, is provided with a coupling member 23 that may be of substantially triangular configuration as seen in front or rear elevation. The coupling member 23 is constructed and arranged for use, in a manner that is known per se, in connecting the implement to the three-point lifting device or hitch at the rear of the agricultural tractor or other vehicle that is used to operate and propel the implement as shown somewhat diagrammatically in Fig. 1 of the drawings.

The top and rear of the coupling member 23 is connected to the top and rear of the hollow frame portion 1 by two steeply downwardly and rearwardly divergent tie beams.

When the implement is to be employed in a cultivating operation, its coupling member 23 is connected to the three-point lifting device or hitch at the rear of an agricultural tractor or other operating vehicle and the rotary input shaft 21 of the gear box 1 9 is placed in driven connection with the rear power take-off shaft of the same tractor or other operating vehicle by way of the known telescopic transmission shaft 22 which has universal joints at its opposite ends.The transmission ratio in the change-speed gear 20 is set to give an appropriate speed of rotation of the soil working members 3 having regard to the nature and condition of the soil that is to be worked and the required depth of cultivation of the latter is set by raising or lowering the level of the axis of rotation of the roller 8 relative to the frame portion 1 by turning the arms 7 upwardly or downwardly, as may be required, about the pivot bolts 6 and maintaining the required setting by entering the retaining bolts through the holes in the side plates 5 which most nearly match the desired setting. It will be apparent that this adjustment principally dictates the maximum depth of penetration of the tines 4 of the soil working members 3 into the soil which is possible when the implement is in use.As previously mentioned, once this adjustment has been made, the shield plates 9 are, if required, re-positioned relative to their carriers 11 to bring their lower edges to a level which is as close as possible to that of the ground surface, the retaining bolts 10 being temporarily removed, re-positioned and tightened to bring this about.

The tines 4 of the two soil working members 3 which are at the opposite ends of the single row thereof co-operate with the respectively neighbouring shield plates 9 in crumbling the worked soil and distributing it substantially uniformly in much the same way as do pairs of neighbouring soil working members 3 at locations which are closer to the centre of the implement. However, the construction that has been described comprises means by which each shield plate 9 can deflect laterally outwardly against the action of the corresponding pair of tension springs 1 7 whilst simultaneously being moved upwardly. This means comprises the pivot pins 1 3 and the co-operating elongate guide slots 14 along which said pivot pins can slide outwardly and upwardly.Since both the bottom of each shield plate 9 and the top of its carrier 11 can move outwardly and upwardly when, for example, a stone becomes momentarily engaged between one of the tines 4 of the neighbouring soil working member 3 and the inner surface of said shield plate 9, that shield plate will normally move outwardly and upwardly without significant, if any, tilting. The horizontal displacement of the plate 9 is, in fact, relatively small so that its relationship with the neighbouring soil working member 3 is temporarily changed only to a minor extent that, generally speaking, interferes with the crumbling and spreading co-operation with said neighbouring member 3 to only a very small degree, if at all.Each shield plate 9 can, however, still turn outwardly and upwardly about the axis defined by the corresponding pair of pivot pins 13, against the action of the tension springs 17, once said pivot pins 1 3 have reached the outer and upper ends of the slots 14. This facility allows an exceptionally larger loose stone, old root or other hard obstacle that may momentarily be trapped between one of the shield plates 9 and the neighbouring soil working member 3 to be released without damage occurring. It will be appreciated that the tension springs 1 7 act to tend to restore the position shown in the drawings so that even a large loose stone or the like will interfere with the crumbling and distributing co-operation between the illustrated shield plate 9 and the neighbouring soil working member 3 only for a very short period of time.

Figs. 4 and 5 of the drawings illustrate a second embodiment in which, however, many of the parts are similar, or identical, to parts that have already been described with reference to the first embodiment, such parts being indicated in Figs. 4 and 5 of the drawings by the same references as are used in Figs. 1 to 3 thereof. In the embodiment of Figs. 4 and 5, the tops of the carriers 11 are somewhat differently shaped to those of Figs. 1 to 3 of the drawings and two supports 24 are connected to said upper edge so as to lie near the front and rear, respectively, of the carrier 11 with respect to the direction A. Each support 24 comprises a pair of parallel upper and lower sleeve-like slideways 25 which slideways 25 are interconnected by a parallel bracket 26.

The two parallel and superposed slideways 25 of each support 24 surround corresponding parallel upper and lower rods 28 and 29 which rods, in their respective pairs, are welded or otherwise rigidly secured to corresponding rod supports 30. The rod supports 30 are, in turn, connected to the top of the hollow frame portion 1 in a manner which is illustrated in outline in Figs. 4 and 5 of the drawings. The two rods 28 and 29 of each pair extend upwardly and outwardly relative to the centre of the implement from the ends thereof which are fastened to the corresponding supports 30 towards their outer free ends and the arrangement is such that the plane which contains the longitudinal axes of the two rods 28 and 29 of each pair is parallel to the companion plane and to a plane which contains the axes of rotation (longitudinal axes) of all of the shafts 2.

In the embodiment which is being described, each rod 28 or 29 is inclined to the underlying ground surface at an angle of substantially 15 and the outermost free end of each rod carries a corresponding stop 31.

Helical compression springs 32 are wound around the portions of the two rods 28 and 29 of each pair which are the immediate neighbours of the stops 31 and said springs 32 bear between those stops and the facing ends of the slideways 25 that movably surround said rods 28 and 29.

Strips 27 which are welded or otherwise rigidly secured to the rods 28 and 29 of each pair constitute stops that prevent the slideways 25 from moving downwardly to the right, as seen in Fig. 4 of the drawings, beyond the position in which they abut against the strips 27.

In this embodiment, each shield plate 9 can, together with the corresponding carrier 11 and pair of supports 24, move upwardly and outwardly, with respect to the centre of the implement, against the action of the compression springs 32 to any position between the limits dictated by the stop strips 27 and stops 31. It will be apparent that the slideways 25 will move slidably, but not turnably, along the two upper rods 28 and two lower rods 29 so that substantially no tilting of the shield plates 9 and carriers 11 will take place.Once again, as in the first embodiment, the shield plates 9 provide the required counterpressure for the soil crumbling and spreading action to take place between those plates and the tines 4 of the immediately neighbouring soil working members 3 and can move outwardly and upwardly to a small extent, without significant tilting, to reduce the coun terpressure, should it tend to become excessive, whilst still maintaining substantially an optimum disposition of the shield plates 9 relative to the neighbouring soil working members 3.A momentarily greater degree of outward and upward displacement of each shield plate 9 and the corresponding carrier 11 is possible, against the restoring action of the springs 32, should a somewhat larger than usual stone, old root or like obstacle become trapped for an instant between one of the plates 9 and one of the tines 4 of the immediately neighbouring soil working member 3, the release of the obstacle thus being facilitated without damage and with very little, if any, interruption to the crumbling and spreading co-operation between the affected plate 9 and the immediately neighbouring member 3.

Although certain features of both embodiments of the soil cultivating implement that have been described and/or that are illustrated in the accompanying drawings will be set forth in the following claims as inventive features, it is emphasised that the invention is not necessarily limited to those features and that it includes within its scope each of the parts of both embodiments of the soil cultivating implements that have been described, and/or that are illustrated in the accompanying drawings, both individually and in various combinations.

Claims (11)

1. A soil cultivating implement of the kind set forth, wherein the or each shield plate is connected to said frame portion in such a way as to allow it to be movable upwardly and outwardly away from the centre of the frame portion without significant tilting.

2. An implement as claimed in claim 1, wherein means which affords said connection between the or each shield plate and the frame portion includes a guide along which a carrier of the shield plate or corresponding shield plate is movable both upwardly and outwardly away from the centre of the frame portion.

3. An implement as claimed in claim 2, wherein there are two guides in respect of the or each shield plate, one being located adjacent the front, and the other being located adjacent the rear, of the carrier or corresponding carrier with respect to the intended direction of operative travel of the implement.

4. An implement as claimed in claim 2 3, wherein the or each guide is in the form of an elongate slot, and wherein the carrier or corresponding carrier is provided with at least one pivot pin which is movable lengthwise along the slot or corresponding slot.

5. An implement as claimed in claim 4, wherein the or each pivot pin is also turnable freely about its own axis in the slot or corresponding slot.

6. An implement as claimed in claim 2, wherein the or each guide takes the form of at least one rod, and wherein an upper region of at least one carrier to which the shield plate or one of the shield plates is connected is provided with at least one sleeve-formation slideway arranged so as to be axially displaceable along the rod or a corresponding one of the rods.

7. An implement as claimed in claim 6, wherein the or each guide comprises two of said rods arranged in superposed but spaced relationship with one another.

8. An implement as claimed in claim 7, wherein the longitudinal axes of the or each pair of rods which correspond to the or each shield plate are contained in a plane which is parallel or substantially parallel to a plane that contains the upwardly extending axes of rotation of a row of said soil working members.

9. An implement as claimed in claim 7 or 8, wherein the or each pair of rods of the or each guide are secured to a common support mounted on the top of said frame portion.

1 0. An implement as claimed in any preceding claim, wherein the or each shield plate is movable outwardly away from the centre of the frame portion against the opposition of resilient restoring means.

11. A soil cultivating implement of the kind set forth substantially as hereinbefore described with reference to Figs. 1 to 3 of the accompanying drawings or with reference to Figs. 1, 4 and 5 of the accompanying drawings.