GB2437481A

GB2437481A - Implement for cultivating soil

Info

Publication number: GB2437481A
Application number: GB0608163A
Authority: GB
Inventors: Jason Stringer
Original assignee: DOWDESWELL ENG CO Ltd
Current assignee: DOWDESWELL ENG CO Ltd
Priority date: 2006-04-26
Filing date: 2006-04-26
Publication date: 2007-10-31
Also published as: GB0608163D0

Abstract

An implement for cultivating soil, the implement comprising a disc 10 having a radially outer region 14 with a radially outer edge, wherein said outer region is curved in the circumferential direction of the disc to form a plurality of troughs 18 and peaks 16. The radially outer edge is formed with at least one tooth for engagement with the soil. The troughs and peaks may be triangular or sinusoidal in circumferential cross-section, and may be uniformly spaced.

Description

PO2S28TJK 20060426 SpAsFi1ed 1 Implement The present invention relates

to an implement suitable for cultivating soil.

Disc harrows having a plurality of disc shaped blades are well known in the agricultural industry. Generally the harrow comprises two rows of concave disc shaped blades for penetration into and mixing of soil.

Modern disc designs are aimed at reducing the labour involved in tillage thereby providing for more cost-effective crop establishment and improvements in profitability. One such design of blade comprises a disc pressed into a generally wavy shape having a plurality of radial peaks and troughs extending from a generally flat centre portion. Such discs give an effective mixing of soil and surface residues.

However, the wavy disc design is not always effective at penetrating the soil, especially where the soil is hard, for example as a result of compaction and/or dry conditions.

Furthermore, when the surface residue is damp, and a positive drive cannot be obtained, the disc can be prevented from rotating, thereby rendering the machine in which they are used less effective.

The present invention provides an implement for cultivating soil which mitigates the above problems.

According to the present invention there is provided an implement for cultivating soil, the implement comprising: a disc having a radially outer region with a radially outer edge; wherein said outer region is curved in the circumferential direction of the disc to form a S..

plurality of troughs and peaks; and wherein said radially outer edge is formed with at least *s'.

*..: one tooth for engagement with said soil.

S S..

S

Preferably said tooth comprises a first edge and a second edge, said first edge being * :..* configured for initial engagement with the soil as the disc is rotated in a first rotational direction.

P02528UK 20060426 SpeAsFi1ed 2 Preferably said troughs and/or peaks are substantially triangular in circumferential cross-section.

Preferably said troughs and/or peaks are substantially sinusoidal in circumferential cross-section.

Preferably the troughs and peaks are uniformly spaced around the circumference.

Preferably the peaks and troughs are of substantially the same amplitude relative to the plane of the disc.

Preferably the peaks and troughs are of varying amplitudes relative to the plane of the disc.

Preferably said first edge of the or each tooth is inclined at an angle to the radius of the disc.

Preferably said second edge of the or each tooth is inclined at an angle to the radius of the disc.

Preferably the or each tooth is substantially saw-tooth shaped in plan.

Preferably the implement has a plurality of teeth equiangularly spaced about the periphery.

Preferably the first edge of at least one said tooth has a radially outermost point at the apex of one of said peaks. S.

: *.. Preferably the first edge of at least one said tooth has a radially outermost point at the bottom *S.S of one of said troughs. *SS.

* * Preferably the first edge of at least one said tooth has a radially outermost point substantially S..

* aligned with the plane of said disc. a

According to another aspect of the invention there is provided a machine for cultivating soil comprising at least one implement according to any previous claim.

P02528UK20060426 SpaAsFiIed 3 The invention will now be described, by way of example only, with reference to the attached figures in which: Figure 1 shows a side view of a wavy disc for soil cultivation; and Figure 2 shows an illustrative plan view of an implement for soil cultivation according to the invention.

In figure 1 a blade for soil cultivation is shown generally at 10. The blade 10 comprises a disc having a generally circular centre region 12, and a generally annular outer region 14. The centre region 12 is planar, and throughout the description the term "plane of the disc" is intended to correspond to the plane of the centre region 12.

The outer region 14 is corrugated or undulating in the circumferential direction to form a plurality of radially extending peaks 16, and troughs 18 equiangularly spaced around the centre portion. The blade 10 is substantially symmetrical about the plane of the disc, the troughs 18 and peaks 16 extending substantially the same distance out of the plane.

The troughs 18 and peaks 16 are generally fan-shaped or triangular in circumferential cross-section.

In figure 2 an implement for cultivating soil is shown illustratively. The implement comprises a generally disc shaped blade 30 similar to the blade 10 described with reference to figure 1.

:. Like the blade of figure 1, the blade 30 comprises a disc having a generally circular and planar centre region 32, and a generally annular outer region 34. The outer region 34 is *I..

corrugated or undulating in the circumferential direction to form a plurality of radially * : ** extending peaks 36, and troughs 38 equiangularly spaced around the centre portion.

The blade 30 is substantially symmetrical about the plane of the disc, the troughs 38 and ::: peaks 36 extending substantially the same distance out of the plane. It will be appreciated, however, that other configurations are possible in which the peaks 38 extend a different distance out of the plane of the disc 30 relative to the troughs 36, and/or in which the peaks! P025281JK 20060426 SpAsFiIed 4 troughs extend varying distances relative to other peaks/troughs.

The troughs 38 and peaks 36 are generally fan-shaped or triangular in circumferential cross-section, although it will be appreciated that other shapes are possible, for example, sinusoidal or saw-tooth.

The centre region 32 is provided with an aperture 40 suitable for location of the disc on a shaft (not shown) of a cultivating machine, such as a disc harrow or the like. The aperture shown is keyed for location of the disc in a press forming tool, or the like, during manufacture. It will be appreciated, however, that in operation the disc may be freely rotatable on the shaft, thereby allowing the disc to rotate as it is drawn over the soil being cultivated. Alternatively the disc may be keyed to a shaft, depending on the application, to allow the disc to be positively located and/or driven.

The outer region 34 of the disc 30 has a radial outer edge provided with a plurality of teeth 50, each of which is configured for engagement with soil, in operation.

Each tooth comprises a first edge 52, a circumferential outer edge 53, and a second edge 54.

The first edge is generally straight and is configured for initial engagement with the soil as the disc is rotated during operation in a first rotational direction A to cultivate the soil. The first edge is angled, relative to the radius of the disc 30, such that the first edge 52 forms an obtuse angle with the circumferential edge 53. The circumferential edges of the teeth prescribe a substantially circular circumferential outer edge of the disc. It will be appreciated that the first edge may be configured tojoin the circumferential edge at an acute angle thereby : ... forming a sharp point for penetrating certain types of soil. * S IS..

* The second edge 54 is configured to assist disengagement of the tooth from the soil, in * operation, after the first edge has penetrated into the soil during rotation of the disc 30 in the

SS

* first rotational direction A. The second edge 54 extends arcuately and inwardly from the circumferential edge 53 to join the first edge of the next tooth 50. Like the first edge the SI.

* second edge is angled obtusely relative to the circumferential edge. Hence, when the disc is rotating in the first rotational direction A, the first edge acts as a leading edge and the second P02528UK 20060426 SpAsFi1ed 5 edge acts as a trailing edge. It will be appreciated, however, that the disc may be operated in a second rotational direction opposite the first, wherein the arcuate second edge, engages with the soil first to provide a different penetrating and mixing action.

The teeth 50 are arranged such that circumferentially adjacent teeth straddle an adjacent peak and trough, with the radially outermost point of the adjacent first edges aligned with the plane of the disc 30. Hence, the first edge of a tooth straddling a peak extends downwardly from that peak, and the first edge of a tooth straddling a trough extends upwardly from that trough.

It will be appreciated that many other configurations are possible, for example, in which adjacent teeth are of different shapes and/or sizes. The teeth could also be arranged with the radially outermost point of adjacent teeth at the apex of a peak and the bottom of a trough respectively, thereby providing two distinct parallel cutting edges in a single disc.

Thus, in typical operation, a plurality of the discs 30 are fitted to a shaft of a disc harrow or the like. As the disc harrow is operated the teeth on the discs 30 engage with and penetrate the soil, thereby enhancing the positive drive to rotate the discs, hence reducing the risk of the disc stopping. The undulations/corrugations of the disc and the alternate arrangement of circumferentially adjacent teeth further enhance mixing of the soil and surface residue. I. I * * *.* *SS. * * **U. IS. S'S.

S

SS

S

S I * ISs S. *

S S I S.5

Claims

P02528UK 20060426 SpAsFi1ed 6 Claims 1 An implement for cultivating

soil, the implement comprising: a disc having a radially outer region with a radially outer edge; wherein said outer region is curved in the circumferential direction of the disc to form a plurality of troughs and peaks; and wherein said radially outer edge is formed with at least one tooth for engagement with said soil.

2 An implement as claimed in claim 1 wherein said tooth comprises a first edge and a second edge, said first edge being configured for initial engagement with the soil as the disc is rotated in a first direction.

3 An implement as claimed in claim 1 or 2 wherein said troughs and/or peaks are substantially triangular in circumferential cross-section.

4 An implement as claimed in claim 1 or 2 wherein said troughs and/or peaks are substantially sinusoidal in circumferential cross-section.

An implement as claimed in any preceding claim wherein the troughs and peaks are uniformly spaced around the circumference. S. * S * I..

6 An implement as claimed in any preceding claim wherein the peaks and troughs are of * S S.,.

substantially the same amplitude relative to the plane of the disc. *.S.

*. * 7 An implement as claimed in any of claims 1 to 5 wherein the peaks and troughs are of varying amplitudes relative to the plane of the disc. _ _. S.

* : 8 An implement as claimed in any preceding claim wherein said first edge of the or each tooth is inclined at an angle to the radius of the disc.

P02528UK 20060426 SpAsFiIed 7 9 An implement as claimed in any preceding claim wherein said second edge of the or each tooth is inclined at an angle to the radius of the disc.

An implement as claimed in any preceding claim wherein the or each tooth is substantially saw-tooth shaped in plan.

11 An implement as claimed in any preceding claim having a plurality of teeth equiangularly spaced about the periphery.

12 An implement as claimed in claim 11 wherein the first edge of at least one said tooth has a radially outermost point at the apex of one of said peaks.

13 An implement as claimed in claim 11 or 12 wherein the first edge of at least one said tooth has a radially outermost point at the bottom of one of said troughs.

14 An implement as claimed in claim 11, 12 or 13 wherein the first edge of at least one said tooth has a radially outermost point substantially aligned with the plane of said disc.

A machine for cultivating soil comprising at least one implement according to any previous claim. * * * I.. IS.. * S IS.. S'S. * IS.

I *1S S. S * * S S.