GB2100105A - Cultivating implement - Google Patents

Abstract

A cultivating implement for loosening the soil without disturbance of the soil surface includes a frame (10, 11) and at least one soil working tool (30) mounted on the frame, the tool including a blade (35) which extends downwards into the soil in a plane parallel to the direction of travel edgewise through the soil, the blade being inclined at an acute angle to the vertical to lift soil lying above the blade. At the lower end of the blade is a foot (50) which has an inclined upper surface (52) at its leading end and an upright side surface (55) parallel to the direction of travel for resisting lateral forces generated on the tool due to the action of the inclined blade on the soil. <IMAGE>

Description

SPECIFICATION Cultivating implement This invention relates to cultivating implements and in particular to cultivating implements for loosening the soil without significantly disturbing the soil surface.

It has been proposed, for exampie in British Patent Specifications Nos. 1,493,346 and 1,574,412 to provide a soil loosening implement having a blade which in use extends downwards at an acute angle to the vertical and is supported at its upper end to be drawn edgewise through the ground. The blade is profiled such that soil above the blade is lifted and loosened without compressing the soil below the blade. Such an implement has been made and marketed by the applicants but it has been found that significant problems arise with this implement due to the lateral forces imposed on the blade during use which are transmitted to the towing vehicle and cause the vehicle to lose stabiiity and crab.

An object of the invention is to provide an improved cultivating implement able to effect sub-surface loosening of the soil.

According to the invention a cultivating implement comprises a frame, and at least one soil working tool mounted thereon including a blade having a portion which, in operation, extends downwardly into the soil in a plane substantially parallel to its direction of travel edgewise through the soil and inclined at an acute angle to the vertical and so as to lift soil lying above the blade, the tool having at the lower end of the inclined portion a foot member with an upwardly and rearwardly inclined upper surface at its leading end and an upright and rearwardly extending side surface, the side surface being substantially parallel to the direction of travel and constituting a bearing surface which, by engagement with the soil, resists lateral forces on the tool due to the action of the inclined blade on the soil.

Preferably the side surface is defined by a replaceable plate mounted vertically on the foot. The forward end of said inclined upper surface of the foot is conveniently in advance of the leading edge of the blade and in advance of said side surface, and the rearward portion of the side surface is to rear of the trailing edge of the blade.

The inclined upper surface of the foot is conveniently formed of a replaceable plate mounted on a body portion and having its leading edge in advance of the body of the foot.

Preferably the blade is formed with an upper upright portion integral with the downwardly inclined portion, the upright portion and the inclined portion being joined by a contiguous curvilinear portion and the upright portion having mounting means for securing the blade to the frame.

A lower portion of the leading edge of the blade may be fitted with a replaceable edge member in the form of at least one plate with a bevelled leading edge.

At the trailing edge of the blade a pivotable member may be mounted, the pivotable member being adjustable to lie in alignment with the blade or at selected inclinations upwardly with respect to the blade. The pivotable member is preferably mounted at the lower end of the blade adjacent a rearwardly extending portion of the foot.

Further features of the invention will appear from the following description of an embodiment of the invention given by way of example only and with reference to the drawings, in which: Figures 1 and 2 are perspective views of a cultivating implement, Figure 3 is a front elevation of the implement of Figs. 1 and 2, Figure 4 is a side elevation of a soil working tool of the implement of Figs. 1, 2 and 3, and Figure 5 is a perspective view of a foot assembly of the implement of Figs. 1-4 to an enlarged scale.

Referring to the drawings a cultivating implement includes a frame arranged to be mounted on the three point linkage of a tractor. The frame has a forward transverse beam 10 and a rearward transverse beam or tool bar 11. On the forward beam 10 are located transversely spaced brackets 1 2 and 1 3 for connection to the lower arms of the three-point linkage (not shown) of a tractor, in known manner. The beam 10 is perpendicular to the direction of travel A of the implement and the rear bar 11 is inclined at an acute angle to the direction of travel A.

The beam 10 and bar 11 are interconnected by longitudinal beams 14 and 1 5, the beam 14 connecting one end of the beam 10 to one end of the bar 11 and the beam 1 5 connecting the other end of the beam 10 to the bar 1 2. As shown the bar 11 is formed in two interconnected portions 1 1 A and 1 1 B having a flanged connection 16. If desired the portion 11 B of the bar 11 may be omitted, as will be described.

The beam 10 and the bar 11 are also connected by a support member or headstock 1 7 of generally truncated triangular form which carries at its forward upper end a bracket 1 8 for attaching the upper link of the three-point linkage.

The rearward end of the bar 11 carries a ground wheel assembly 20 including a pivotal arm 21 and a height adjustment device 22, a ground engaging wheel 23 being mounted at the end of the arm 21 to support the frame, when the implement is in use, at an adjustable height relative to the ground surface.

Mounted on the bar 11 at positions equally spaced along the bar 11 are, in this case, four cultivating tool assemblies 25. Each of the assemblies 25 is the same and due to the inclination of the bar 11 to the direction of travel A the assemblies are in echelon, that is, each assembly is to the rear and one side of the preceding assembly.

Each tool assembly 25 is mounted on the bar 11 by a fixing plate 26 located over the bar 11, the plate 26 being secured to a body 27 located under the bar by four fixing bolts 28, the body 27 extending parallel to the direction of travel A. Towards the rear of the body 27 is attached by bolts 29 a cultivating tool 30, shown in more detail in Fig. 4. The forward end of the body 27 carries a rotatable disc 32 for opening up an inclined slit in the ground in advance of the tool 30. The disc 32 is carried on an arm 33 which is springloaded downwardly to resiliently urge the disc towards the ground in the operative position of the implement and form a vertically inclined slit in the ground aligned with the opening to be made in the ground by the tool 30.

Referring now particularly to Fig. 4 the cultivating tool 30 includes a blade portion 35 formed of steel plate and having an upright portion 36 apertured at 37 for bolting by two bolts to the body 27, one of the bolts being a shear bolt arranged to shear in the event that the tool 30 meets an obstruction. The portion 36 extends vertically and is integral with an inclined portion 38 being joined thereto by a curvilinear portion 39. The blade 35 is formed of high grade steel so that adequate strength is achieved with a relatively thin section thereby giving rise to a relatively narrow opening in the ground surface after the blade has been drawn edgewise through the ground.

The inclined portion 38 of the blade constitutes a working portion and the portion 38 is of tapered shape towards its lower end. The leading edge 41 of the portion 38 is angled so that at its lower end it is further forward in the direction of travel than at its upper end and, due to the tapering of the portion 38, the trailing edge 42 of the portion 38 of the blade is angled forward to a greater extent than the leading edge 41.

At the leading edge 41 a bevel 43 is formed to receive replaceable leading edge members 44. At the trailing edge 42 the portion 38 is provided with hinge brackets 45 by which an adjustable flap or lifting plate 47 is attached to the tool.

Three contiguous leading edge members 44 are provided along the edge 41, each bolted through holes 48 to the portion 38 and each member 44 having a bevel 49 whereby as the tool is drawn through the ground the soil is more readily lifted up as it passes over the tool. The lower ground engaging surface of each member 44 is flat and contiguous with the lower side of the portion 38 and lies parallel to the direction of travel. In this way the soil under the tool is not significantly compressed during the passage of the tool.

The flap 47 is for selectively increasing the soil lifting action of the tool. The flap 47 is in the form of a plate having welded along one edge a tube 48 through which passas a hinge pin which engages at its ends in the brackets 45. Thus the flap 47 is able to be pivoted about the hinge axis, which lies parallel to the plane of the portion 38, from a position in which the flap is aligned with the blade portion 38 and exercises no additional lifting action on the soil, to a position in which the flap is raised about the axis. In the raised position the upper surface of the flap 47 lies above the upper surface of the portion 38 and gives an extra lifting action on the soil passing over the upper side of the tool.

The flap 47 is retained in a selected raised position by a screw (not shown) whose axis is at a right angle to the plane of the flap and which screw is screwed in and out and engages the underside of the flap. The flap 47 has its lower edge lying horizontally at the lower end of the blade portion 38 the other edges of the flap being shaped to provide a generally truncated triangle, narrowing towards its trailing edge.

In certain circumstances the flap may be omitted from the tool.

A foot assembly 50, see particularly Fig. 5, is welded to the lowermost end of the blade and the assembly 50 serves to guide and stabilise the movement of the tool through the ground. The assembly 50 includes a body member 51 to which various replaceable wearing members are secured. At the leading end of the body 51 is attached an upwardly and rearwardly inclined plate 52 fixed by bolts to the body. The plate 52 has a leading bevelled edge 53 and the inclination of its upper surface ensures that when the tool enters the ground the tool moves downwardly and is positioned and maintained at the selected depth in the soil. The plate 52 is located on a portion of the body 51 which protrudes forwardly of the leading edge of the blade. To each side of the inclined plate 52 are located side plates 54 attached to the body 51.

The body 51 extends rearwardly to protrude from the trailing edge of the blade adjacent the lower edge of the flap 47 (if present).

Along one lateral side of the body 51 is located a plate 55 which acts as a bearing member to resist the lateral thrust on the tool arising from the reaction on the inclined blade during movement through the soil. Such thrust acts in a direction to tend to straighten the blades i.e. in the direction B in Fig. 3.

The plate 55 is attached to the body by bolts 56 and the plate extends vertically and parallel to the direction of travel. The plate 55 presents a lateral face which engages the soil alongside the foot to resist the lateral thrust B.

It will be seen that said lateral face is of substantial surface area in relation to the size of the foot sufficient to counter the lateral thrust of the associated blade which differs according to the blade length and angle of inclination and the nature of the soil.

Thus the foot assembly 50 performs three main functions in causing the tool to maintain the desired depth, in counteracting the lateral thrust on the tool which would otherwise cause a turning moment on the implement frame and make the towing tractor tend to crab in its movement over the ground, and in assisting initial penetration of the tool into the ground.

The implement described and shown in the drawing is able to effect a loosening effect on the soil over a substantial width, the tools interacting with each other to cultivate over the width of the implement. If desired the width may be reduced by omitting one of the tools by dismounting the portion 11 B of the bar 11. A tool 25 may also be used on its own or in other combinations.

The loosening action arises due to the lifting of the soil above the blade or blades which puts the soil in tension and causes fracture and cracks in the soil without significant disturbance of the soil surface. To achieve this soil loosening effect the blade is inclined in a direction transverse to the direction of travel at an angle between about 25-60" to the vertical.

In an alternative arrangement the foot may be releasably attached to the blade and formed in one piece, as for example by forging, so that upon wear of the foot surfaces the foot is replaced. In another arrangement a replaceable wearing part is employed in which the leading edge and the side surfaces are formed as a single replaceable part which fits over the body of the foot and is releasably secured thereto. Such a replaceable part may have an opening in the nature of a socket into which the body fits, the body being urged into engagement with the socket during use.

Such an arrangement enables a simple securing member to be used to hold the part on the body.

Claims (11)

1. A cultivating implement comprising a frame, and at least one soil working tool mounted thereon including a blade having a portion which, in operation, extends downwardly into the soil in a plane substantially parallel to its direction of travel edgewise through the soil and inclined at an acute angle to the vertical and so as to lift soil lying above the blade, the tool having at the lower end of the inclined portion a foot member with an upwardly and rearwardly inclined upper surface at its leading end and a substantially upright and rearwardly extending side surface, the side surface being substantially parallel to the direction of travel and constituting a bearing surface which, by engagement with the soil, resists lateral forces on the tool due to the action of the inclined blade on the soil.

2. A cultivating implement according to claim 1 wherein the side surface of the foot is defined by a replaceable plate mounted vertically on the foot.

3. A cultivating implement according to claim 1 or 2 wherein the forward end of the inclined upper surface of the foot is located in advance of the leading edge of the inclined blade portion and in advance of said side surface.

4. A cultivating implement according to any one of claims 1,2 or 3 wherein the rearward end of said side surface is to the rear of the lower end of the trailing edge of the inclined blade portion.

5. A cultivating implement according to any one of the preceding claims wherein the inclined upper surface of the foot is defined by a replaceable plate mounted on a body portion of the foot and having its leading edge in advance of said body portion.

6. A cultivating implement according to any one of the preceding claims wherein the blade includes an upper upright portion integral with the downwardly inclined portion, the upright portion and the inclined portion being joined by a contiguous curvilinear portion and the upright portion having mounting means for securing the blade to the frame.

7. A cultivating implement according to any one of the preceding claims wherein towards the lower end of the inclined blade portion is fitted at least one replaceable leading edge member having a bevelled leading edge.

8. A cultivating implement according to any one of the preceding claims wherein a pivotable member is mounted at the lower end of the inclined blade portion, the pivotable member being adjustable to lie in alignment with the plane of the blade or at selected inclination upwardly with respect to said plane and the pivotable member being of generally triangular shape narrowing in the upwards direction.

9. A cultivating implement according to claim 10 comprising a headstock arranged for attachment to the top link of a tractor three point linkage, the headstock extending between and being attached to leading and rear frame members and extending upwardly of the frame members at its leading end.

10. A cultivating implement according to claim 9 wherein the rear frame member is inclined at an acute angle to the direction of travel and at its rearward end is attachable to an extension member arranged to carry at least one of said soil working tools.

11. A cultivating implement substantially as described with reference to the drawings.