AU659564B2 - Bearing for a disc harrow - Google Patents

Description

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AUSTRALIA

Patents Act 1990 8 r COMPLETE SPECIFICATION FOR A STANDARD PATENTT 01 -Rone-l~n~la~ BONE-L-La-MVP "a L (nIe c Name of Applicant: Actual Inventor: Address for Service: ;Invention Title: t EDWARD ANDREW BONEL CULLEN

CO.,

Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

BEARING FOR A DISC HARROW 0e 0 The following statement is a full description of this invention, including the best method of performing it known to us: ii-- THIS INVENTION relates to a bearing housing arrangement for use in agricultural implements such as disc harrows and the like.

A disc harrow typically comprises one or more rows of discs, each row of discs being mounted on a common axle. The discs are spaced apart by tubular spacer members mounted concentrically with the axle.

Long bolts or tie rods pass through the disc/spacer combination, and hold the combination together axially.

Bearings are provided to permit rotation of the discs relative to the frame of the disc harrow, and there are two principal types of bearing arrangements used in known disc harrows. In the first type, the bearings are mounted on the axle, and the outer bearing housings are mounted to the harrow frame by respective dropper brackets. The discs, spacers and axle are able to rotate in combination. This bearing arrangement is sometimes known as the "rotating axle" type.

In an alternative construction, known as the "stationary axle" arrangement, the axle is fixed to the harrow frame by suitable dropper brackets or the like.

Bearing assemblies are mounted on opposite ends of the axle, and the outer bearing housing of each bearing assembly is connected to the outside of the last disc at that respective end of the row of discs. In the stationary axle arrangement, the discs (and spacers) are able to rotate relative to the axle.

However, it has besn found that the bearing assemblies used in either the stationary or rotating axle 30 configurations require regular servicing and maintenance, and have uncertain durability. As these bearings are continually exposed in use to dust, dirt and other contaminants, they are prone to failure, and should therefore be replaced regularly in a preventative maintenance program.

It is an object of the present invention to provide a new bearing mounting arrangement for an agricultural implement such as a disc harrow, r;

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i particularly of the stationary axle type, which overcomes or ameliorates the abovedescribed disadvantages or which at least provides the consumer with a useful choice.

In one broad form, the present invention provides an agricultural implement comprising a plurality of ground engaging members spaced along a common axle and spaced apart by spacer members, the ground engaging members and spacer members being rotatable about the axle, characterised in that the implement further comprises at least one bearing device mounted between the axle an. a spacer member and located within the spacer member.

In the preferred embodiment, the implement is a disc harrow and the ground engaging members are the steel discs normally used on such disc members. The spacer members are formed by pipe sections sandwiched between the discs. The common axle passes through the discs and Sspacers, and the disc/spacer assembly is held together axially by a series to tie rods extending therethrough.

Tha axle is mounted to the frame of the disc harrow, typically by fixing to spaced dropper brackets.

In this manner, the axle is fixed relative to the frame, and tle spacer/disc combination is rotatable about the common axle.

Unlike known disc harrows and similar implementn having exposed bearings, the bearing in the implement of this invention is located in a substantially closed space, namely within a spacer and between two discs. Typically, a bearing is provided at each end of the axle, between the last two discs at that end.

Any suitable bearing may be used. The inner race sleeve of the bearing is suitably mounted on the axle, while the outer sleeve of the bearing is rigidly connected to the inside of the spacer. Such connection may be made by radial arms extending between the outer sleeve of the bearing and the inside of the spacer.

These arms are suitably designed to allow for passage therethrough of the axial tie rods. i P- 4 In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described with reference to the accompanying drawings, in which: Fig. 1 is a side elevational view of a disc row for a disc harrow embodying the invention; and Fig. 2 is a sectional elevation of a bearing mounting of Fig. 1.

As shown in Fig. 1, a disc row for a disc harrow, such as a tandem offset disc harrow, comprises a series of curved steel discs 11 spaced apart by spacers 12. Each spacer 12 is typically a length of metal pipe.

The spacer/disc assembly is held together axially by a series of tie rods 13 extending longitudinally therethrough and tightened by bolts at one or both ends thereof.

The disc/spacer assembly is mounted on a common shaft or axle 14. The free ends of the axle 14 are normally mounted to the frame of the disc harrow, e.g. by fixing to a pair of spaced dropper brackets. In this manner, the axle 14 is held stationary relative to the frame, while the disc/spacer assembly is rotatable about the axle.

Bearings 15 are provided between the axle 14 and respective spacers 12. Each bearing is located within its associated spacer, within the substantially o oo closed space defined by the spacer and the discs at either end of the spacer. Typically, the bearings 15 are located in the spacers between the last two discs at each end of the row.

The bearing arrangement is shown in more detail in Fig. 2. To mount the bearing 15, an annular fitting 16 is first fixed by welding) to the interior of a spacer pipe 11. The radial portions of this fitting suitably include apertures for the passage therethrough of the tie rods. The fitting 16 includes a step against which the bearing 15 locates. A circlip 17 retains the bearing 15 in its axial position. Sleeve fittings 17, 18 are threaded together to provide a mounting for the bearing 17 on the axle 14. Suitable oil seals 19 and dust seals 20 are also provided.

A closable access socket 21 is provided in the spacer pipe 11 to provide access to a greasG nipple 22 on the bearing from outside the spacer pipe 11. Thus, although the bearing 15 is located within a substantially closed space, it is still accessible for greasing. The bearing fitting may also include an oil bath for continuous lubrication of the bearing.

The bearings permit the spacer/disc assembly to rotate about the common axle 11. As each bearing is located within the closed space defined by its spacer and the discs on either side thereof, the bearing is protected from dirt, dust and other deteriorating factors. Consequently, the life of the bearing is prolonged, and servicing requirements are reduced to a minimum level.

The foregoing describes only one embodiment of the invention and modific,- ions which are obvious to those skilled in the art may be made thereto without departing from the scope of the invention as defined in V' the following claims.

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Claims (9)

1. An agricultural implement comprising a plurality of ground engaging members spaced along a common axle and spaced apart by spacer members, the ground engaging members and spacer members being rotatable about the axle, characterised in that the implement further comprises at least one bearing device mounted between the axle and a spacer member and located within the spacer member.

2. An implement as claimed in claim 1, wherein the axle is mounted to the frame of the implement and is stationary relative thereto.

3. An implement as claimed in claim 2, further comprising a plurality of tie members extending longitudinally through the spacer members and the ground engaging members to hold them together axially, the ground engaging members and spacer members being collectively rotatable around the axle.

4. An implement as claimed in any preceding claim, wherein the bearing device comprises an inner sleeve mounted on the axle and an outer sleeve connected to the inside of the spacer member.

An implement as claimed in any preceding claim wherein the implement is a disc harrow and the ground engaging members are curved discs, the spacer members being tubular sections.

6. An agricultural implement as claimed in claim wherein a bearing device is located generally at each end of the axle within the spacer member between the last two discs at that end.

7. An implement as claimed in any preceding claim, wherein an aperture is provided in the spacer member in radial alignment with a grease nipple on the bearing device to provide access to the grease nipple from without the spacer member.

8. An implement as claimed in any preceding claim, wherein the bearing device includes an oil bath for lubrication thereof. 7

9. A disc harrow comprising a frame, a shaft mounted to the frame and fixed relative thereto, a plurality of discs orientated generally transversely to the axle and spaced therealong by tubular spacers positioned between the discs and generally concentrically with the axle, the discs and spacers being bound axially by one or more tie rods; characterised in that the disc harrow comprises at least one bearing mounted between the axle and a spacer member, and located within the substantially closed space defined by the spacer member and the discs on either side thereof. An agricultural implement substantially as hereinbefore described with reference to the accompanying drawings. DATED this twenty-second day of July 1993 DT D i <-BNE-LMITEBD A93T By their patent attorneys CULLEN CO. Li 1 4 0 0 I 'I ABSTRACT A disc harrow comprises a series of discs (11) spaced apart by tubular spacers The discs (11) and spacers (12) are mounted on a common axle (14) by bearings Each bearing is located in a spacer (12) within the substantially closed space defined by the spacer (12) and the discs (11) at either end thereof. The bearing is therefore shielded from dust, dirt and other contaminants, thereby prolonging its useful life. ,4