WO2005096800A1

WO2005096800A1 - Stubble crusher reel and support frame

Info

Publication number: WO2005096800A1
Application number: PCT/AU2005/000005
Authority: WO
Inventors: Colin Harper
Original assignee: Colin Harper
Priority date: 2004-04-05
Filing date: 2005-01-06
Publication date: 2005-10-20

Abstract

A stubble reel (11, 13, 17, 19) having a longitudinal axis about which the reel (11, 13, 17, 19) can be rotated, the reel (11, 13, 17, 19). comprising a pair of rigid end blade supports (31), the central axis of the supports (31) being common with the central axis of the reel (11, 13, 17, 19); longitudinally extending blades (21) having a ground engaging cutting edge (23), each blade (21) is affixed to the end blad5 supports (31) near the periphery of each support (31), with the cutting edges (23) located beyond the periphery of the end blad5 supports (31) and the cutting edges are substantially equidistant from the central axis of the reel and regularly spaced around the central axis; one or more intermediate blad5 supports (33, 35), each support (31) holding a blade (21) in a fixed position relative to another blad5 (21) and an inner axial support member (25) extending along the central axis and connected to the end blad5 supports (31). Also disclosed is a support frame for the stubble reel (11, 13, 17, 19), the frame having a frame body (5) and a pair of support arms (43), each arm (43) having a first end pivotally attached (47) to the frame body (5) and a second end for attaching a rotatable stubble cutting reel (11, 13, 17, 19) between the pair of arms (43), the support frame including at least one resilient member (57) between the frame body and each support arm (43) for biasing the ground engaging blad5s (21) of an attached reel (11, 13, 17, 19) into ground engaging contact.

Description

"Stubble Crusher Reel and Support Frame"

Field of the Invention

The present invention relates to equipment for knocking down and cutting or splitting stubble.

Background to the Invention

Stubble is the plant residue left on the ground after harvesting crops, typically grains. As the stubble can interfere with the operation of most cultivation or sowing machines, particularly the lower cost machines, the stubble needs to be flattened or removed before sowing the field.

One method has been to simply collect or burn off the stubble. However, in a number of jurisdictions farmers have or are facing a complete ban on stubble burning. As there are few uses for stubble and since it is generally not economic to transport stubble in bulk farmers will generally return the stubble into the ground from where crop was grown.

Farmers can use many different machines to process the stubble including ploughs, slashers, harrows, prickle chains, cable and rubber tyre rollers. Some machines such as ploughs will incorporate the stubble into the ground, and other machines such as tyre rollers merely flatten it. The different machines process different types of stubble with varying degrees of effectiveness. Some machines are cumbersome or inefficient to use and may require several passes or the use of additional equipment. For example, ploughs may be used to bury the stubble but will only treat a small area in a single tractor trip and can require the use of a harrow to smooth the soil and break up earth clods arising from ploughing.

Rice 'stubble' also causes problems. After harvest the stubble remains alive and continues to absorb moisture making it more difficult to prepare the field for re-use. Farmers may use slashers to cut down the rice stubble. Farmers may also use rice rollers to crush and break the stubble and kill the plants so the plants will not continue to absorb moisture. A rice roller is a machine normally used to prepare rice beds before sowing. A rice roller normally has a single heavy elongate drum of over 1 metre in diameter and several meters in length with short radially extending iron blades along the length of the drum. The blades are used to form divots into which the rice seeds will gather after the field is flooded and air sown. The rice rollers may also be used to kill rice stubble although its size and mass make it heavy and difficult to manoeuvre and difficult to transport.

Another type of agricultural roller is described in US Patent No. 6,119,788 (Bernier). This patent describes a gang of three rollers in a triangular formation for use in levelling the earth. The rollers omit any blades.

US Patent No. 4,479,554 (Kueker) describes a towed device for crimping and fixing mulch. The machine omits a roller and instead uses an array of toothed cutting discs.

US Patent No. 4,249,613 (Kueker) describes a machine for forming agglomerates of earth of a desired average size. The device includes a first set of small reels having ten radially extending blades and a second set of reels having ten N' shaped blades.

US Patent No. 5,632,343 (Gengler) describes a disc cultivator having fitted thereto a hexagonal reel. The reel is located after the cultivator and is used to deflect and level soil thrown up by the cultivator discs.

There has also been described a small number of machines, which may be referred to as stalk choppers, for specifically processing grain stubble. One of the earliest is US Patent No. 308,306 (Davis). The machine has two reels each fitted with six blades for towing behind horses. A three reeled wing is described in US Patent No. 1,287,374 (McHam). Another three reeled wing is described in US Patent No. 2,118,363 (Schwarz). Each reel has six blades, the blades affixed between two hexagonal blade supports. Another variation is described in US Patent No. 2,741,887 (Denton) which uses a first reel located in front of a second reel in a line. Each reel is a frustoconical portion. US Patent No. 4,150,724 (Strobel) includes two rows of four shredder reels, each reel having six radially extending blades. It is thought the bulk of the machine would make it difficult to manoeuvre.

A stubble-processing machine used to a limited extent in Australia has a horizontal line of drum rollers formed from 300 mm pipe attached to a harrow frame. Each roller included along its length eight regularly spaced short blades, each blade extending radially from the side of the drum. The blades were formed from star pickets (elongate steel rods having a " Y" shaped cross-section) wherein two of the three arms of the picket were welded to the drum so the third arm provided a short blade. Unfortunately, the machine was not sufficiently robust or effective for wide scale commercial operation.

There remains a need for a manoeuvrable machine capable of efficiently flattening, cutting or splitting stubble so the stubble will not interfere with the subsequent use of cultivation or sowing equipment.

Brief Description of the Invention

In an embodiment of the invention there is provided a longitudinally extending stubble reel having a longitudinal central axis about which the reel can be rotated, wherein the reel comprises:- a pair of longitudinally spaced apart rigid end blade supports having a periphery, the central axis of the supports being common with the central axis of the reel; seven, eight or nine longitudinally extending blades, wherein each blade has an outer ground engaging cutting edge; wherein each blade is affixed to the pair end blade supports at or near the periphery of each support, with the cutting edges located beyond the periphery of the end blade supports and in an arrangement wherein the cutting edges are substantially equidistant from the central axis of the reel and substantially regularly spaced around the central axis; one or more intermediate blade support(s), each support holding at least a blade in a fixed position relative to another blade; and optionally including an inner axial support member extending along the central axis and connected to the end blade supports.

Preferably the distance from the central axis to the cutting edge is from 150 mm to 300 mm, more preferably from 175 mm to 300 mm, more preferably from 200 to 275 mm, most preferably about 200 to 250 mm. Of this distance, preferably the cutting edge is located between 25 mm and 75 mm beyond the periphery of the end blade supports, more preferably about 50 mm. This provides a reel having a diameter of from 300 to 600 mm measured from cutting edge to cutting edge and a typical size around 400 mm.

The reel may have seven, eight or nine blades, and preferably eight.

For effective operation of the machine it is thought to be important to use the preferred number of blades and the preferred reel diameter. The reel can be difficult to use, transport and manoeuvre if the reel diameter is too large. A large diameter reel also uses significantly more steel in its assembly and in the number of blades. If the reel is too small it may not effectively flatten the stubble and, in use, the rapid rate of rotation of the reel may place undue stresses on any support apparatus. A small diameter reel may only roll over the stubble and may not cut or crush the stubble, or may only crush the stubble at one point along a blade, reducing the rate of degradation and breakdown of the stubble.

The number of blades also affects overall crushing and cutting efficiency and the "smoothness" of its operation. The more blades on the reel, the less bouncy its operation as it rolls over the field. However, too many blades will result in more blades engaging the ground at any one time which decreases the crushing and cutting force applied to stubble. In operation it is preferred to only have the cutting edge of one blade of the reel engaging the ground to transfer to maximum crushing and cutting forces on the stubble. Preferably the stubble will be cut or crushed by the cutting edge every 125 to 150 mm of its length, more preferably every 150 mm (six inches).

Preferably the end blade supports are discs or octagonal in shape, more preferably are discs. Preferably the faces of the end blade supports and any primary blade support are substantially perpendicular to the central axis. Preferably the thickness of the support at the periphery is no more than 15 mm and more preferably no more than 10 mm.

The combination of a reel of a diameter of about 400 mm (± 30 mm) measured from opposite cutting edges, the use of eight regularly spaced apart and radially extending blades is considered to be particularly advantageous.

The cutting reel includes at least one intermediate blade support. The intermediate blade supports can comprise one or more additional primary blade supports and / or one or more secondary blade supports. A primary blade support is attached to all blades and may also be attached to the optionally inner support member. The primary blade support may take the form of a solid disc or other flat shape or may be open and include spokes or other connecting elements. A secondary blade support connects two blades in a fixed position relative to each other. Preferably the reel includes both primary blade supports and secondary blade supports.

Preferably the blades can have an overall length of from 40 mm to 110 mm, preferably from 60 mm to 90 mm, and more preferably from 70 to 80 mm. Preferably the blades are set back into the periphery of the end blade supports and any primary blade supports, preferably by up to half the length of the blade, and position the cutting edge from 25 mm to 75 mm from the periphery of the end blade supports.

Preferably the width of the blades is not more than 15 mm, more preferably no more than

10 mm. Preferably the blades have a bevelled edge, the end of which provides the cutting edge of the blade. Preferably the blades are bevelled at 50° to 70° angle, more preferably a 60° angle. Preferably the width at the cutting edge is no more than 3 mm and preferably is 2 mm.

Preferably the width of reel is from 2 to 3 metres and more preferably of from 2.2 to 2.8 metres, and more preferably about 2.5 metres. Preferably the pair of primary blade supports is located at the ends of the reel and the longitudinal length of the blades is substantially the same as the width of the reel. It is preferred for each of the blades to be integral members, but a blade may be composed of two or more elongate blade segments, fastened together or otherwise held together to provide an elongate length of blade.

The reel may include outer shafts extending outwards along the central axis from the outer faces of the two end blade supports. These outer shafts may be used as axles for rotatably attaching the reel to a reel support structure. Alternatively the reel may include a central bore in the outer faces of the end pair of blade supports into which an axle or axles may be positioned to rotatably attach the reel to the support structure. The bore may be located in only the end blade supports or the bore may form a hole extending along the length of an inner axial support member connected to the end blade supports. The axle may itself form part of the optional axial inner support member.

In an alternative embodiment the shafts extend from a bearing assembly affixed to or incorporated in the two end blade supports. The free outer ends of the shafts are intended to be fixably held by a reel support structure with the other end rotatably held within the bearing assembly. The bearing assembly may be a tapered roller bearing, which can take heavy loads. This arrangement can simplify the service and maintenance requirements as the main parts that would wear and require service and maintenance, namely the blades and rotating bearing assembly are all part of the reel. The reel support structure would be largely unchanged. When the reel includes such bearing assemblies, the two end blade supports may be located flush with the longitudinal ends of the blades, or more preferably set back into the reel, in order to provide additional space for the bearing assemblies with the free outer ends of the support shafts extending beyond the longitudinal ends of the blades. The longitudinal ends of the blades may extend 100 to 200 mm past the end blade supports. The free ends of the blades may be adequately supported by the end blade supports due to the proximity of the end supports and the strength/rigidity of the blades. However, in a preferred arrangement the extended ends of the blades may include secondary blade support members at or near the ends of the blades.

In another embodiment of the invention there is provided a stubble roller having a longitudinally extending central axis about which the roller can be rotated, the roller comprising a longitudinally extending cylindrical body having a central axis common with the axis of rotation of the roller, the cylindrical body having a diameter of from 250 to 350 mm, preferably 300 mm, and having eight cutting blades radially extending from the outer surface of the cylindrical body, the blades being substantially regularly spaced about the outer surface of cylindrical body and extending along the width thereof, wherein each blade has an outer ground engaging cutting edge, and the cutting edges of the blades located at least 40 mm, more preferably at least 50 mm, from the outer surface of the cylindrical body.

The particulars of the cylindrical body and of the blades thereon are as described earlier for the reel.

In operation the reel (and also the above described roller) can subject stubble to both a flattening force and also a crushing / cutting force. In use the reel will roll over the stubble and typically the forces involved in the rolling action will stop it from again standing upright. However, when combined with a cutting edge and with sufficient downward force, the roller can cut the stubble or at least crush it breaking open the stalks. This has the advantage of mulching the stubble, promoting decomposition whilst allowing the use of typical cultivator machines in the field. It is not necessary to sever the stubble, nor is it possible for most plants (other than canola). However, it is sufficient to crush and break open the plant in at least one location, more preferably twice, in order to promote degradation of the plant and reduce the fire danger. In another embodiment of the invention there is provided a support frame for the reel or roller as described above, the frame having a frame body and a pair of longitudinally spaced apart support arms, each arm having a first end pivotally attached to the frame body and a second end adapted for attaching a rotatable stubble cutting reel or roller between the pair of arms, the support frame including at least one resilient member between the frame body and each support arm for biasing the ground engaging blades of an attached reel or roller into ground engaging contact.

Preferably each arm has a separate resilient member for biasing the reel or roller into ground engaging contact.

Preferably the support frame includes at least one upstanding member attached to the frame body and having an upper end with one end of the resilient member connected thereto, the other end of the resilient member being connected to a support arm for biasing the arm downward.

Preferably the resilient member is a coil spring. Preferably, one end of a shaft is pivotally connected to a support arm and the shaft is restrained within a bore in a mounting bracket connected to the upper end of the upstanding member, the shaft having fitted thereon the coil spring which is restrained at one end by the mounting bracket and is restrained at the other end by a spring restraint attached to the shaft. The shaft can slide within the bore to permit relative movement of the arm to the mounting bracket but is prevented from being withdrawn from the bore by a restraint attached to the shaft above the mounting bracket. The bias provided by the coil spring can then be adjusted by changing the position of the spring restraint on the shaft. In a preferred arrangement the shaft is threaded and the position of the spring restraint can be changed by relocating a nut on the shaft.

The reel or roller may rotate within the frame by being rotatably attached to the second end of the arms or by the frame being fixably attached to a portion of the reel or roller which is rotatably attached to the remainder of the reel or roller, such as by rotatable bearing assembly. In another embodiment of the invention there is provided a reel or roller support frame of the invention as described above having a reel or roller of the invention attached thereto.

In a further embodiment of the invention there is provided an agricultural machine comprising an 'A' frame and two wing frames attached on either side of the A frame; the A frame and the wing frames including support frames of the invention as described above, connected thereto, each frame having a reel or roller of the invention rotatably attached thereto.

Preferably the 'A' frame includes a support frame and each wing includes at least one support frame. More preferably each wing includes at least two support frames.

It will be understood that when the machine includes a plurality of reels or rollers, the reels or rollers will need to be spaced apart from each other. The reels or rollers can be located in a row along the width of the machine. However, to avoid leaving narrow, long sections of unprocessed stubble along the length of a processed field, it is preferable to offset at least some of the reels or rollers so as to provide cutting blades along the entire width of the machine. This can be done by locating some of the reels or rollers in a first row, with the remainder in a second row, with the rollers or reels of the second row located to bridge across the gaps between adjacent rollers of the first row.

In a preferred form of the invention the frame body of the reel or roller support frames is integral with the A frame and wing frames.

One of the benefits of including resilient members in the support frame is it allows for the application of a greater cutting or crushing force on the stubble. Each of the most preferred reels weighs around 250 kg. The preferred dimensions are such only one cutting edge engages the ground at any one time. As each reel is approximately 2.5 m in length then the reel only applies 100kg per m of blade. This is not considered sufficient to provide the desired amount of damage (crushing or cutting) to the most types of stubble to promote decomposition.

The weight of each reel (or roller) could be increased but this would reduce the manoeuvrability of the machine. Larger, heavier reels or rollers also require additional reinforcement of the reel / roller support frame and the A frame and wing frames. In addition it will increase the manufacturing and operation (fuel) costs.

A proportion of weight of the support frame and A frame and wing frames can be transferred from support wheels to the cutting blade by using the resilient members in the support frame. Preferably the downward bias of the resilient members results in a total downward force of approximately 200 kg / m of cutting blade.

Example embodiments of the invention will be now be described with reference to the accompanying figures in which:-

Brief Description of the Figures

Fig. 1 is a perspective view of the agricultural machine of the invention, including reel support frames and reels of the invention. The machine is shown in the transportation configuration.

Fig. 2 is a perspective view of the agricultural machine of figure 1, arranged in the operational configuration.

Fig. 3 is a perspective view of a portion of the agricultural machine of figure 2.

Fig. 4 is another perspective view of a portion of the agricultural machine of figure 2. Fig. 5 is a perspective view of an alternative embodiment of a reel of the invention.

Detailed Description of the Invention

The invention will now be described with reference to the above figures.

Figure 1 shows the agricultural machine (1), the stubble cruncher, arranged for transportation. The A frame (3) and wing frames (5, 7) are based on a harrow frame, in particular a K-line 2500 series harrow bar. The machine includes five cutting reels (11, 13, 15, 17 and 19). Wing frame (5) has two cutting reels (11, 13), frame (7) has two reels (17, 19) and the A frame includes cutting reel (15). The cutting reels are held within support frames forming part of the A and wing frames.

The wing frames are suspended above the ground and rotatably attached at either side of the A frame at the back of the frame 'I AT at the points (9), in the transportation configuration. The wings fold out from either side of the A frame by pivoting, by rotation about 90°, about points (9) such that the wings outwardly extend from the frame at the points (9) '_A_\ The wings are then rolled over about their elongate axis, rotating approximately 90° to locate the reels (11, 13, 17, 19) near to the ground. This action also orientates the upright members (65) into the upright position. The wheels (77) are used to support and guide the wings when folding and unfolding. These support wheels are raised off the ground when the wings are rotated to raise the upright members (65) and lower the reels. The wheels (75) then contact and support the wing frames. The extension movement and rotation of the wings can be done with hydraulics, the hydraulic hoses (78) being visible in the figures.

Figures 2, 3 and 4 show the machine with the wings extended and rotated into the operational position. The reels have eight blades (21) (not all are visible) radially extending and evenly spaced about a central pipe (25) of 110 mm diameter.

Each blade has a cutting edge (23) which is substantially horizontal when the reels are positioned for use. The cutting edges are provided by bevelling the free ends of the blades. The angle shown is 60°, although other angles may be used. Thus the cutting edge has a flat face common with the blade (27) and an angled face (29). In operation the reels contact the ground and the machine is pulled by a tractor by the front end of the A frame (10). The motion of the machine and the contact of reels with the ground will result in the rotation of the reels as the machine is pulled by the tractor. In normal operation the flat face of the blades should be the face which first engages the ground, although the reel can still operate, although less effectively, if it is fitted back to front so the angled face first strikes the ground.

The blades have width (thickness) at the cutting edge of 2 mm. The blades have a width of around 10 mm in the non-bevelled portion. The blades are made from strong, long wearing steel, such as bisaloid steel. The longitudinal (horizontal) length of each blade is 2.5 m. The blades (21) together with the end discs (31) and intermediate blade supports (33, 35) form the cutting reels. The cutting reel also includes a central shaft (25), although this shaft can be omitted or replaced with other rigid members for strengthening the reel assembly.

The depicted reels include two types of intermediate blade supports. The reels include primary supports (33), which are circular discs welded (39) to the central shaft (25) and a portion of the blades (40). If the central shaft is omitted the disc is simply affixed to each of the blades. Likewise, the end discs (31) are welded to the central shaft (25) and a portion of the blades. The supports locate the blades from the central axis of the reel and locate the cutting edges about 50 mm (2 inches) beyond the rims of the end and primary supports.

The rims defining the periphery of the supports are approximately 10 mm in width. This width when combined with two end supports and two primary supports providing four rims will normally support the reels on the ground, preventing them from extending into the ground beyond the rims. However, the open structure of the reels will permit parts between the rims to extend into the ground when the ground is uneven. Furthermore, should a rim be travelling along a peak, the concentration of downward force on that rim may permit the rim to extend into the ground and enhance overall performance of the reel on uneven surfaces.

The secondary supports are individual sections (35) welded to two adjacent blades. Eight sections 32 mm in length and 8 mm in width are used to additionally support the blades and hold them in a spaced-apart relationship. In use the blades may contact rocks or other hard objects and the reinforcement provided by the primary and secondary supports together with the end supports should prevent the blades from flexing or unduly bending. However, should a blade be damaged it is expected the machine will still function, albeit less effectively. If severely damaged the blade could be removed in total or the damaged section could be removed and may be replaced with a similar sized segment of blade and fastened to the remainder of the damaged blade.

Each cutting reel (11) is approximately 2.5 m in width and 400 mm in diameter measured from the cutting edge to cutting edge and weighs approximately 250 kg.

Each reel rotates about axles (41) extending from the ends of the reel. The axles extend into holes located near an end of paired arms (43) which support the reel at one end and which are pivotally attached to the A-frame (for the centrally located reel) or the wing frames (for the other reels) at the other end. The other ends of the arms (43) are pivotally attached to brackets (46) extending from and forming part of the frames by the shaft (45). The axles extend through the holes and have enlarged ends (42) to prevent the separation of reels from the support arms.

Each of the arms (43) is also attached to a pivoting bracket (47) by shaft (49). Attached to and extending from the pivoting brackets (47) is threaded shaft (51), which is restrained by nuts (53) and (55). Around the shaft is located a coil spring (57) which is restrained at one end by a disc (59) attached to the shaft, the location of which is controlled by nut (61).

The other end of the spring (57) is restrained by a mounting bracket (63) attached to an upright member (65). The upright members (65) are directly welded to the A frame for the members associated with reel (15), the wing frames (5) and (7) for reels (19) and (11) respectively, or to the frame extensions (81) connected to the wing frames for reels (13) and (17). In figure 3 the depicted upright member (65) is welded via a mounting bracket (67) near the end of the wing frame (5). The bracket (63) includes an aperture (69) through which the other end of the shaft (51) passes. The size of the aperture permits the sliding movement of the shaft (51) through the aperture as the reels and arms move relative to the A or wing frames, but does not permit the enlarged end of the shaft (71) to pass back through. This arrangement is repeated for each support arm of each reel.

As shown in figure 2, reels (13) and (17) are set in a row which is offset from reels (11, 15 and 19), which are set in another row. This provides as staggered, set back arrangement with the ends of the reels of the two rows overlapping to avoid leaving a gap between reels along the width of the machine and thereby avoid leaving narrow strips of stubble between adjacent reels. The reels (13) and (17) are located in an offset row by using shaft extensions (81) attached to and forming part of the wing frames (5) and (7), and having attached thereto the reel support frame with the pivoting arms (43) and reels (13, 17).

In operation the machine is supported by A frame wheels (73) and the reels (5). The wing wheels (75) may also support the frame, although the force applied via the coil springs can be such to lift the ends of the wing wheels off the ground.

The embodiment has been described by way of example only and modifications are possible within the scope of the invention. One such variation is depicted in figure 5. The depicted reel omits the central shaft but includes eight longitudinally extending blades (21), the two end disks (31), additional primary supports (33) comprising discs which are welded to each of the blades and secondary blade supports (35, 36).

Unlike the earlier depicted reels, the two end disks each include a bearing assembly (77), about which the reel can rotate. The bearing assembly forms part of the end discs and support shafts (79) extend from both assemblies for attachment to support arms. The bearing assemblies and attached discs and the reel can rotate about the support shafts (79).

In order to provide space for the bearing assembly on either end disk, end disks are set into the reel so that the longitudinal ends of the blades extend pass the end disks by 150 mm.

The support shafts (79) extend beyond the longitudinal ends of the blades for fastening to paired arms of a support frame similar to that shown in figures 1 to 4. The longitudinal ends of the blades are held together by the secondary supports (36).

Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers.

Claims

1. A longitudinally extending stubble reel having a longitudinal central axis about which the reel can be rotated, wherein the reel comprises :-

a pair of longitudinally spaced apart rigid end blade supports having a periphery, the central axis of the supports being common with the central axis of the reel;

seven, eight or nine longitudinally extending blades, wherein each blade has an outer ground engaging cutting edge;

wherein each blade is affixed to the pair end blade supports at or near the periphery of each support, with the cutting edges located beyond the periphery of the end blade supports and in an arrangement wherein the cutting edges are substantially equidistant from the central axis of the reel and substantially regularly spaced around the central axis;

one or more intermediate blade support(s), each support holding at least a blade in a fixed position relative to another blade;

and optionally including an inner axial support member extending along the central axis and connected to the end blade supports.

2. The stubble reel according to claim 1 wherein the distance from the central axis to the cutting edge is from 150 mm to 300 mm.

3. The stubble reel according to claim 2 wherein the distance from the central axis to the cutting edge is from 200 to 250 mm.

4. The stubble reel according to claim 1 wherein the cutting edge is located between 25 mm and 75 mm beyond the periphery of the end blade supports.

5. The stubble reel according to claim 1 wherein the reel has eight blades.

6. The stubble reel according to claim 5 wherein the end blade supports are discs or have an octagonal shape.

7. The stubble reel according to claim 1 wherein the reel has eight regularly spaced apart and radially extending blades and a diameter of from 370 to 430 mm measured from opposite cutting edges.

8. The stubble reel according to claim 1 wherein the reel includes secondary blade supports which connects two blades in a fixed position relative to each other.

9. The stubble reel according to claim 1 wherein the reel includes primary blade supports which are attached to all blades of the reel.

10. The stubble reel according to claim 1 wherein the blades can have an overall length of from 40 mm to 110 mm.

11. The stubble reel according to claim 1 wherein the width of the blades is not more than 15 mm.

12. The stubble reel according to claim 1 wherein the blades have a bevelled edge, the end of which provides the cutting edge of the blade.

13. The stubble reel according to claim 1 wherein the blades are bevelled at 50° to 70° angle and the width of the blade at the cutting edge is no more than 3 mm.

14. The stubble reel according to claim 1 wherein the width of the reel is substantially the same as the longitudinal length of the blades and is from 2 to 3 metres.

15. The stubble reel according to claim 1 wherein the reel includes a means by which the reel can be rotationally fastened to a support frame.

16. The stubble reel according to claim 15 wherein each of the end blade supports includes a bearing assembly having an outwardly extending shaft for attacliment to a support frame and arranged so that the blades can rotate about the central axis about the bearing assemblies.

17. A support frame for a stubble reel, the frame having a frame body and a pair of longitudinally spaced apart support arms, each arm having a first end pivotally attached to the frame body and a second end adapted for attaching a rotatable stubble cutting reel or roller between the pair of arms, the support frame including at least one resilient member between the frame body and each support arm for biasing the ground engaging blades of an attached reel or roller into ground engaging contact.

18. The support frame according to claim 17 wherein each arm has a separate resilient member for biasing the reel or roller into ground engaging contact.

19. The support frame according to claim 17 wherein the support frame includes at least one upstanding member attached to the frame body and having an upper end with one

^• end of the resilient member connected thereto, the other end of the resilient member being connected to a support arm for biasing the arm downward.

20. The support frame according to claim 17 wherein the resilient member is a coil spring.

21. An agricultural machine comprising an 'A' frame and two wing frames attached on either side of the A frame, the A frame and the wing frames including reel support frames according to claim 17 connected thereto, each frame supporting a reel according to claim 1.

22. The agricultural machine of claim 21 wherein the 'A' frame includes a support frame and each wing includes at least one support frame.

23. The agricultural machine of claim 22 wherein each wing includes at least two support frames.

24. The agricultural machine of claim 23 wherein the wings are capable of movement between an operation configuration wherein each wing extends outward from a side of the A frame and blades of the reels are capable of ground engaging contact, and an transportation configuration wherein each wing is located along the sides of the A frame and the reels supported in the wings are not capable of ground engaging contact.

25. The agricultural machine of claim 24 wherein when the machine is in the operation configuration, the reels are located in two rolls, with the first, third and fifth reel located in one roll, and the second and fourth reel in the other row.

26. The stubble reel, frame or machine substantially as hereinbefore described with reference to the figures.