AU771302B2 - Harvest residue destruction system - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Address of Applicant: HARVESTAIRE PTY LTD 18 MUMFORD PLACE BALCATTA WA 6021 PHIL ZANI Griffith Hack, Patent and Trade Mark Attorneys, 6th Floor, 256 Adelaide Terrace, Perth, Western Australia, 6000.

Actual Inventor: Address for Service: Standard Complete Specification for the invention entitled: HARVEST RESIDUE DESTRUCTION SYSTEM Details of Associated Provisional Applications: PQ 7073 dated 20 April 2000 The following is a full description of this invention, including the best method of performing it known to me:- -2- HARVEST RESIDUE DESTRUCTION SYSTEM The present invention relates to a harvest residue destruction system particularly for use with an agricultural harvester, and more specifically, though not exclusively a weed seed destruction system.

In recent years, there has been an increasing problem with rye grass and other weeds becoming resistant to selective and non-selective herbicides. This has led to a reduction in crop yields with a resulting loss of income for affected farmers. This problem has developed where continuous cropping has been carried on for a long period of time with continual use of herbicides.

oeeee 0 Numerous different techniques have been proposed for managing this problem. Some of the techniques available for farmers wishing to continuously crop their land, are: applying 15 paraquat mixture as prior to harvest; collecting weed seeds during harvesting and then appropriately disposing of them; incorporating a pasture rotation for grazing to control seed development or hay production; or, modified tillage practices to encourage germination of weed seeds prior to main seeding.

0 0' 20 The present Applicant has recently developed a further mechanism for destroying weed seeds as described in their patent application No. 37966/95. In this system, a pair of 0 counter-rotating rollers is used to crush weed seeds that have been previously separated from the crop being harvested, chaff and other unwanted material.

While sound in theory, the use of counter-rotating rollers to crush weed seeds has proven very difficult to implement. In order to prevent jamming or damage to the rollers, it is necessary for one of them to be supported by some type of bias mechanism, typically a spring. This will allow for example, the passage of a pebble or small rock that would otherwise jam or damage the rollers. Thus the spring bias must be sufficient to allow the 3 0 rollers to move apart to allow foreign objects to pass but must be able to provide sufficient pressure to crush the seeds passing therethrough. It has been found that at times when a volume of seeds passing between the rollers, seeds in the middle of the volume are protected by seeds on the outside and are either not crushed at all or are not crushed sufficiently to make them non-viable. A further drawback with the roller system is that the seeds only pass through once. Therefore if a seed is not crushed, it remains in a viable state.

It is an object of the present invention to provide a system for destroying the residue from a harvest to the extent that the residue or selected components thereof is rendered nonviable.

According to the present invention there is provided a harvest residue destruction system for an agricultural harvester having a primary separator for separating harvest residue from an agricultural crop being harvested, said destruction system including at least: disintegrating means for disintegrating said residue into a plurality of particles of a size to render the weed seed non-viable, said disintegrating means having a first member 15 and second member adapted to rotate relative to each other, said first member juxtaposed with said second member to define a disintegration zone therebetween, said first member ooooo provided with a first set of spaced apart first teeth and said second member provided with a second set of spaced apart second teeth, said sets of teeth being interleaved and extending into said disintegration zone, the disintegrating means further having an inlet 20 and an outlet spaced by at least a portion of said disintegration zone whereby harvest residue entering the inlet is disintegrated by impacting with and between said teeth as it travels from said inlet to said outlet when said first member is rotated relative to said second member.

In one embodiment the disintegrating means includes a power input means adapted for connection to the power source that powers the harvester. However in an alternate embodiment the system includes a separate power source for powering said disintegrating means.

In one embodiment, said first member includes a first disc and said first set of first teeth are arranged as a plurality of radially spaced concentric rings of first teeth extending from one side of said first disc; and said second member includes a second disc with said -4second set of second teeth formed as a plurality of radially spaced concentric rings of second teeth extending from a surface of the second disc facing the first disc.

Preferably the first member is provided with a peripheral wall extending continuously about the periphery of the first disc, the peripheral wall spaced from a radially closest ring of second teeth by a distance substantially greater than the particle size of the disintegrated seeds to form said outlet Alternately said first member is provided with a peripheral wall extending continuously about the periphery of the first disc, and said peripheral wall is provided with one or more windows which form said outlet.

.oo.oi Preferably said peripheral wall is in the shape of an involute curve.

15 Preferably said first disc is a stator and said second disc is a rotor.

o•,o• In one embodiment of the invention, said first disc and first set of teeth are integrally formed and/or said second disc and second set of teeth are integrally formed.

20 In an alternate embodiment, said first disc and first teeth are formed separately and/or said second disc and said second teeth are formed separately.

Preferably said first and second teeth are formed as individual teeth which are separately mounted on said first and second discs respectively.

In another embodiment, said first and second teeth are formed as respective integral rings of teeth wherein said rings of teeth are removably coupled to respective ones of said first and second discs.

Preferably said rings of teeth are in the form of annular rings having opposite first and second axial ends and provided with a plurality of spaced apart axially extending slots, said slots disposed inboard of said first and second opposite axial ends wherein said teeth comprise axially extending portions of said annular rings disposed between adjacent slots.

Preferably said first and second discs are provided with respective grooves for seating said annular rings.

In an alternate embodiment, said first member includes a cylinder and said first set of first teeth extend radially inward from an inner circumferential surface of said cylinder, the first teeth spaced circumferentially about and axially along the cylinder; and said second member has an outer circumferential surface disposed within said first cylinder with said second set of second teeth extending radially outward from said outer circumferential surface, the second teeth spaced circumferentially about the and axially along said outer circumferential surface with said first teeth interleaving with said second teeth.

Preferably said teeth are twisted along their length so as to induce a helical path motion of 15 seeds or other material flowing from said inlet to said outlet. However in an alternate embodiment said first teeth, or said second teeth or both said first and second teeth are arranged in a helical path.

Preferably said destruction system further includes secondary separating means for 20 separating weed seeds from the residue prior to entering said disintegrating means.

Preferably said secondary separating means includes one of: a reciprocating sieve; a rotating mesh cylinder; an air separation system; a centrifugal separating system; or a combination of two or more thereof.

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is an elevational section of a harvester rear end provided with a seed destruction system in accordance with the prior art; -6- Figure 2 is a side view of a harvester incorporating a seed destruction system in accordance with the present invention; Figure 3 is a section view of the disintegrating unit; Figure 4 is a plan view of a stationary disc incorporated in a first embodiment of a disintegrating unit incorporated in the seed destruction system shown in Figure 2; Figure 5 is a plan view of a rear end of a harvester incorporating a first embodiment of a feed arrangement for the weed seed destruction system; Figure 6 is a plan view of a rear end of a harvester incorporating a second .000. embodiment of a feed arrangement for the weed seed destruction system; o S Figure 7 is a schematic representation of portion of a second embodiment of the disintegrating unit.

Figure 8 is a schematic representation of portion of a third embodiment of the disintegrating unit.

Figure 9 is a schematic representation of portion of a fourth embodiment of the disintegrating unit.

Figure 10 is a schematic representation of portion of a fifth embodiment of the disintegrating unit.

The Applicant's prior seed destruction system is illustrated in Figure 1 mounted on a harvesting machine 10. The harvesting machine 10 includes a straw walker 12, which carries straw 14 to be discharged beneath the harvester 10 after being deflected downwardly by a baffle 16. The straw walker 12 is the uppermost of three sieves, releasing crop kernels from the straw 14 and other matter picked up by the harvester -7- Below the straw walker 12 is a middle sieve 18 and a lower sieve 20. Air 22 is also delivered by a blower to blow air from beneath the sieves 18 and 20. This forms a winnowing system by which clean grain kernels pass through the sieves 18 and 20 onto a lower inclined plate 24 leading to an auger 26 that in turn delivers the clean grain to a storage bin. The less dense chaff, straw and weed seeds 30 are carried by the straw walker 12, and sieves 18 and 20 to be finally delivered into a hopper 32. A pair of counterrotating rollers 34 as provided at the bottom of the hopper 32 through which the seeds pass. As the seeds 30 pass through the rollers 34 they are crushed and then dropped back onto the ground.

As mentioned above, the rollers 32 have practical limitations adversely effecting their ability to consistently render non-viable a large proportion of the weed seeds .o.o Figures 2-4 illustrate a destruction system 34 in accordance with the present invention mounted on a harvester 10. In these and the remaining figures, like reference numbers are used to denote like features. This embodiment is directed to weed seeds but has application for all harvest residue. The harvester 10 in Figure 2 is of a structure similar to the harvester shown in Figure 1 and includes sieves 18 and 20, plate 24, auger 26, hopper 28 and baffle 16. The straw walker 12 depicted in Figure 1 is also included in the 0" 20 harvester 10 but is not illustrated. The destruction system 34 is mounted near the hopper 28 on the harvester 10 for receiving, weed seeds 30 separated from other harvest residue directed in the hopper 28.

System 34 includes a disintegrating means 36 for disintegrating the seeds 30 into a plurality of particles of a size so as to render the seeds 30 non-viable. As shown in greatest detail in Figures 3 and 4, the disintegrating means 36 includes a first member in the form of a stationary disc 38 provided with a plurality of radially spaced concentric rings 40a-40d (referred to in general as "rings 40") of teeth 42, and a second member in the form of a rotary disc 44 also having a plurality of radially spaced rings 46a-46d of teeth 48. The discs 38 and 44 define a disintegration zone 45 therebetween. The rings 46 of teeth 48 of the rotary disc 44 interleave with the rings 40 of teeth on the stationary disc 38 as depicted in Figure 3. In this particular embodiment the disc 44 and teeth 48 are integrally formed from a single block of material as the disc 38 and teeth 42. But as explained later the teeth may be formed separately from and demountably connected to respective discs.

A gap 50 is provided between adjacent teeth 42 in each of the rings 40 on the stationary disc 38. Likewise, gaps (not shown) exist between adjacent teeth 40 in each of the rows 46 of the rotary disc 44. Seed inlet 52 is provided in the middle of the stationary disc 38 from which the seeds 30 collecting in the hopper 38 enter the disintegrating unit 36. A seed outlet 54 is formed about the periphery of the stationary disc 38. However it is envisaged in an alternate embodiment that the outlet is formed for only a portion of the periphery of the disc 38 and further be formed as a single outlet or a series of outlets about the periphery.

iSeeds entering through the inlet 52 are caused to move radially outwardly by centrifugal force created by the rotation of the rotary disc 44. In order to reach the outlet 54, the seeds must pass through the disintegration zone 45, ie between the gaps 50 of teeth 42 (as well as the gaps between the teeth 48). As a seed extends through a gap 50 it is collected by a rotating tooth 48. It is believed that this causes a rapid acceleration of the seed causing it to explode and thus disintegrate. It is also believed that rapid deceleration of a seed as it strikes a stationary tooth causes the seed to explode.

The outlet 54 in this embodiment is formed by providing a peripheral wall 56 extending continuously about the periphery of the stationary disc 38 and spaced from the radially outermost ring 46a of teeth 48 by a distance substantially greater than the particle size of the disintegrated seeds. The disc 38 and wall 36 are shown as being of constant radius, but they may also be formed in the shape of an involute curve.

The rotating disc 44 is provided with means, in this instance, a hub 58 to allow connection with the power source of the harvester 10. This can be effected in numerous ways including by way of pulleys and belts, or providing the hub 58 with an hydraulic motor to enable driving of the disintegrating unit 36 by the standard hydraulics of the harvester or auxiliary hydraulics added to the harvester -9- At the lower end of the hopper 28 is an auger 58 for directing the seeds collected in the hopper to the seed inlet 52. In the arrangement shown in Figure 5, the auger 58 is provided with flights 60 and 62 extending along different halves of the auger 58 with flights 60 and 62 wound in an opposite sense so as to direct the seeds collected in the hopper toward the centre of the hopper for discharge into inlet 52 of an underlying disintegrating unit 36.

In an alternate arrangement shown in Figure 6, two disintegrating units 36a and 36b are provided with the auger 58 having four sets of flights 64, 66, 68 and 70 extending in series each for a quarter of the length of the auger 58 and with alternating sense so that flights 64 eeeei and 66 direct seeds toward inlet 52 of the first underlying disintegrating unit 36a while flights 68 and 70 direct seeds to the inlet 52 by the second underlying disintegrating unit 36b.

Figure 7 depicts an alternate embodiment of the disc 38 and teeth 42. In this embodiment, .eee.i the disc 38 and teeth 42 are formed separately and demountably attached together. The disc 38 is provided with multiple apertures 39 each of which accommodates a single tooth 42. The apertures 39 are formed in concentric rings. The apertures 39 in each ring are S 20 joined by respective shallow annular grooves 41. Each tooth 42 is provided with a root 43 in the shape of a round peg which, typically, is held within a respective aperture 39 by an interference fit. This can be achieved by heating the disc 39 to expand the diameter of the apertures 39 and then lowering the teeth 42 into respective apertures 39. A small laterally extending locating pin 45 is provided on the root 43 of each tooth for seating within the locating groove 41. This prevents rotation of the tooth 42 within this aperture 39 and also provides a stop to the downward motion of the teeth 42 when being inserted into the apertures 39. Upper portion 47 of the teeth 42 which extend from the root 43 are slightly tapered so as to reduce in width in a direction away from the root 43. This tapering is provided on three surfaces of the upper portion 47. A main impacting face 51 of each tooth 42 can have brazed to it a tungsten coating. A corresponding disc 44 and teeth 46 (not shown) can also of course be formed in the same manner as depicted in Figure 7.

Figure 8 illustrates a further variation of the embodiment depicted in Figure 7. This embodiment differs by the inclusion of a square locating shoulder 53 between the round peg-like root 43 and upper portion 47 of each tooth 42. In addition, the locating groove 41 in this embodiment is widened to accommodate the square locating block 53. It will be appreciated that the square locating should 53 functions in effect in the same manner as the pin 45 in preventing rotation of the teeth 42 within the apertures 39.

Figure 9 depicts yet a further embodiment of the disintegrating unit 36. In this embodiment, the disc 38 and teeth 42 are again formed separately. However, in contrast with the embodiments shown in Figures 7 and 8, the teeth 42 are formed in a plurality of integral annular rings 40 which are individually bolted to the discs 38. Each ring 40 has ~opposite axial ends 55 and 57. A plurality of spaced apart axially extending through slots °59 are formed in each ring 40 inboard of the axial ends 55 and 57. The portion of the rings between adjacent slots 49 constitute the teeth 42. Axial end 55 is formed with an 15 increased thickness in order to allow the provision of a threaded hole 61 for receiving a bolt 63 to enable demountable coupling of each ring 40 to the disc 38. The disc 38 is provided with a series of grooves 41 for accommodating the axial ends 55 in a plurality of spaced apart through holes for accommodating the bolts 63. The disc 44 is formed in a similar manner to the disc 38 and rings 46 similar to rings 40 are provided to form the teeth 48 for the disc 44.

The axial end 57 forms a continuous annular rib joining the ends of teeth 42 distant the axial end 55. This substantially eliminates deflection of the teeth 42 which may otherwise lead to failure of the disintegrating unit. In addition this enables the teeth 42 to be made higher and thinner which increases the capacity of the disintegrating unit 36 for a given diameter. As further depicted in Figure 9, the end 57 substantially resides within recesses or spaces formed below inside surface 65 of the disc 44 which faces the disc 38.

Figure 10 depicts a further embodiment of the disintegrating unit 36a. In this embodiment, the first member of the disintegrating unit is in the form of a cylindrical stator 38a provided with a plurality of concentric rings of teeth 40a. The teeth in each ring are circumferentially spaced from each other and extend radially inwardly from an -11inner peripheral surface of the stator 38a. Adjacent rings 40a are spaced axially along the stator 38a. The second member is in the form of a cylindrical rotor 44a which is disposed inside the stator 38a. The rotor 44a is also provided with a plurality of concentric rings of teeth 46a. The teeth 46a extend radially outwardly from an outer circumferential surface of the rotor 44a. The teeth in each ring 46a are spaced circumferentially from each other about the rotor 44a. Further, adjacent rings of teeth 44a are spaced axially from each other. The rows of teeth 40a interleave with the rings of teeth 46a. The space between the outer circumferential surface of rotor 44a and inner circumferential surface of stator 38a defines the disintegration zone 45a. The disintegrating unit 36a is provided with an inlet 52a at one end of the disintegration zone 45a and an outlet 54a at an opposite end. The teeth in the rings 40 and 46a may be twisted but their length so as to define a helical flow path between the inlet 52a and outlet 54a.

In order to maximise the efficiency of the said destruction system 34, it is preferable to 15 reduce as much as possible an amount of foreign matter other than weed seeds entering the disintegrating unit 36. This can be achieved in the present system 34 by the addition of a S"secondary mechanical separator 72 at the top of the hopper 48. The separator 72 acts to allow passage of the weed seeds 30 to the exclusion ofchaffand other foreign matter. The separator 72 is in the form of a reciprocating sieve which is driven by the sieve 18.

Alternately it is envisaged that the separator 72 may be independently driven by hydraulics or via belts so that its speed of reciprocation can be varied.

By disintegrating the weed seeds 30 into a plurality of smaller particles, it is believed that the present system 34 operates with greater efficiency and effectiveness than the use of counter-rotating rollers employed in AU 37966/95. As the seeds 30 must pass through a plurality of rings of teeth, it is more likely that they will be impacted upon and subsequently fragmented on several occasions prior to exiting the disintegrating unit 36.

Now that embodiments of the present invention have been described in detail, it will be apparent to those skilled in the relevant arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the embodiment described in relation to Figures 1 and 2 includes a straw walker 12.

-12- However, the inclusion of the straw walker is not essential to the present invention and indeed many harvesting machines to which embodiments of the present invention may be incorporated do not have a straw walker. In addition, the outlet 54 of the disintegrating unit is described and illustrated as being in the form of a space or gap between the peripheral wall 56 and the radially outermost ring of teeth 48. However in an alternate form, the peripheral wall 56 may be adjacent the radially outermost ring of teeth (or edge of disc 44) with the outlet 54 formed by providing one or more windows in the peripheral wall 56.

All such modifications and variations together with others that would be obvious to a person of ordinary skill in the art are deemed to be within the scope of the present invention, the nature of which is to be determined from the above description and the appended claims.

Claims (17)

1. A harvest residue destruction system for an agricultural harvester having a primary separator for separating harvest residue from an agricultural crop being harvested, said destruction system including at least: disintegrating means for disintegrating said residue into a plurality of particles of a size to render the weed seed non-viable, said disintegrating means having a first member and second member adapted to rotate relative to each other, said first member juxtaposed with said second member to define a disintegration zone therebetween, said first member provided with a first set of spaced apart first teeth and said second member provided with a second set of spaced apart second teeth, said sets of teeth being interleaved and 00*00: "•:•extending into said disintegration zone, the disintegrating means further having an inlet and an outlet spaced by at least a portion of said disintegration zone whereby harvest residue entering the inlet is disintegrated by impacting with and between said teeth as it 15 travels from said inlet to said outlet when said first member is rotated relative to said second member. ooJo•

2. A harvest residue destruction system according to claim 1 wherein said first member includes a first disc and said first set of first teeth are arranged as a plurality of radially spaced concentric rings of first teeth extending from one side of said first disc; and said second member includes a second disc with said second set of second teeth formed as a plurality of radially spaced concentric rings of second teeth extending from a surface of the second disc facing the first disc.

3. A harvest residue destruction system according to claim 1 or 2 wherein the first member is provided with a peripheral wall extending continuously about the periphery of the first disc, the peripheral wall spaced from a radially closest ring of second teeth by a distance substantially greater than the particle size of the disintegrated seeds to form said outlet.

4. A harvest residue destruction system according to claim 1 or 2 wherein said first member is provided with a peripheral wall extending continuously about the periphery of -14- the first disc, and said peripheral wall is provided with one or more windows which form said outlet.

A harvest residue destruction system according to any one of claims 1 to 4 wherein said peripheral wall is in the shape of an involute curve.

6. A harvest residue destruction system according to any one of claims 2 to 5 wherein said first disc and first set of teeth are integrally formed and/or said second disc and second set of teeth are integrally formed.

7. A harvest residue destruction system according to any one of claims 2 to 5 wherein said first disc and first teeth are formed separately and/or said second disc and said second teeth are formed separately. 15

8. A harvest residue destruction system according to claim 7 wherein said first and second teeth are formed as individual teeth which are separately mounted on said first and second discs respectively.

9. A harvest residue destruction system according to claim 7 wherein said first and second teeth are formed as respective integral rings of teeth wherein said rings of teeth are removably coupled to respective ones of said first and second discs. 0. a

10. A harvest residue destruction system according to claim 9 wherein said rings of teeth are in the form of annular rings having opposite first and second axial ends and provided with a plurality of spaced apart axially extending slots, said slots disposed inboard of said first and second opposite axial ends wherein said teeth comprise axially extending portions of said annular rings disposed between adjacent slots.

11. A harvest residue destruction system according to claim 9 or 10 wherein said first and second discs are provided with respective grooves for seating said annular rings.

12. A harvest residue destruction system according to claim 1 wherein said first member includes a cylinder and said first set of first teeth extend radially inward from an inner circumferential surface of said cylinder, the first teeth spaced circumferentially about and axially along the cylinder; and said second member has an outer circumferential surface disposed within said first cylinder with said second set of second teeth extending radially outward from said outer circumferential surface, the second teeth spaced circumferentially about the and axially along said outer circumferential surface with said first teeth interleaving with said second teeth.

13. A harvest residue destruction system according to claim 12 wherein said teeth are twisted along their length so as to induce a helical path motion of seeds or other material flowing from said inlet to said outlet. *eo

14. A harvest residue destruction system according to claim 12 wherein said first teeth, or said second teeth or both said first and second teeth are arranged in a helical path.

A harvest residue destruction system according to any one of claims 1 to 14 further 0 0including secondary separating means for separating weed seeds from the residue prior to entering said disintegrating means.

16. A harvest residue destruction system according to claim 15 wherein said secondary separating means includes: o .a reciprocating sieve; a rotating mesh cylinder; an air separation system; a centrifugal separating system; or a combination of two or more thereof.

17. A harvest residue destruction system substantially as herein described with reference to and as illustrated by Figures 2-10 of the accompanying drawings. Dated this 20th day of April 2001 HARVESTAIRE PTY LTD By Its Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia.