AU2021221806A1

AU2021221806A1 - An impact rotor and associated material processing system

Info

Publication number: AU2021221806A1
Application number: AU2021221806A
Authority: AU
Inventors: James Barr; Nicholas Berry; Benjamin Morris
Original assignee: Seed Terminator Holdings Pty Ltd
Current assignee: Seed Terminator Holdings Pty Ltd
Priority date: 2021-08-25
Filing date: 2021-08-25
Publication date: 2023-03-16
Also published as: WO2023023807A1; CA3229985A1; AU2022332714A1

Abstract

An impact rotor for a material processing system and capable of rotating about a rotation axis comprising: a base plate; a first circular array of hollow impact bars disposed about the rotation axis, wherein one end of each impact member is coupled to the base plate; each impact bar is provided with a continuous outer surface being coated with hard facing; and a first support ring coupled to an opposite end of each impact bar. 12 10 16a 24a 24b 8 14 9 20 2 26 FIG 1 10 24a 18 39 41 FIG2

Description

10 16a

24a

24b

8

14 9

20 2 26 FIG 1 10

24a 18

39

41 FIG2

AN IMPACT ROTOR AND ASSOCIATED MATERIAL PROCESSING SYSTEM

TECHNICAL FIELD An impact rotor and an associated material processing system are disclosed. The material processing system has particular, but not exclusive, application for the devitalisation of weed seeds and fragmentation of organic matter. In such applications the rotor and processing system may be mounted on a combine harvester to process a chaff stream.

BACKGROUND ART Weeds and weed control are, and always have been, one of the biggest constraints and costs to grain production. Weeds are a perpetual problem that limits the food production capacity of agricultural area around the globe. Weeds compete with the cultivated crops for water, sunlight and nutrients. In the past 50 years there has been a shift from tillage being the most important method to control weeds to herbicides being the most important tool to control weeds. Herbicides in general provide much better control of weeds than tillage methods and do not have the major issues of soil erosion, moisture loss and breakdown of soil structure. The widespread use and reliance of herbicides has resulted in weeds evolving resistance to herbicides. The herbicide resistance is now widespread and presents one of the biggest threats to global food security. Strategies to provide non-chemical weed control to complement herbicides are now paramount to reduce the selection pressure for herbicide resistance. One particular method of significant renewed interest is destroying weed seeds at harvest time to interrupt the weed cycle.

Many in-crop weeds share a similar life cycle to harvested crops. Once a crop matures and is harvested, there is a broad range of weeds that have viable seeds remaining on the plant above the cutting height of the harvester. These weeds enter the harvester and their seeds either end up in a grain tank, out with straw residues, or out with chaff residues. There are a range of factors that determine where a weed seed will end up at harvest time including moisture content, maturity, and harvester setup. A major factor that determines where a seed ends up is the aerodynamic properties of the seeds or its terminal velocity. Often a weed seed is much lighter than the grain being harvested. Crop cleaning systems used during harvesting employ a winnowing action to remove light chaff material from the heavier grain using airflow and mechanical sieving. The light weed seeds are caught in the wind and can exit the back of the harvester sieve. The residues and contained weed seeds are then spread on the ground to be a problem for next year. The residues also contain a proportion of grain being harvested that could not be separated by the harvester. This grain loss has the potential to become a volunteer weed after harvest. There is an opportunity to intercept and destroy weed seeds in the residues before allowing them to become a problem for next year's crop.

One method to destroy these weed seeds is to use a milling technology. Milling technology has been used for particle size reduction of a range of feedstock for over a century. Milling technology can be separated into crushing and impact technology.

One system for seed destroying mill technology is described in WO 2018/053600 (Berry). Berry describes a weed seed processing system in the form of a multistage hammer mill. This mill has a plurality of milling stages arranged concentrically about each other. The plurality of milling stages is arranged so that substantially all material in a first inner most of the milling stages passes through all subsequent adjacent milling stages. The milling stages include a first milling stage and a second milling stage. A central feed opening enables material flow into a primary impact zone of the first milling stage. The first milling stage has an impact mechanism and a first screen arrangement. The impact mechanism rotates about a rotation axis. The first screen arrangement is disposed circumferentially about and radially spaced from the impact mechanism and is provided with a plurality of apertures through which impacted material of a first size range can pass. The second milling stage has a second arrangement disposed circumferentially about and radially spaced from the first screen arrangement and a circular array of impact elements disposed between the first screen arrangement and the second screen arrangement.

This system has proved to be effective in the field and installed on combines in many countries. The disclosed impact system was developed with the view to enhancing the performance material processing systems including, though not limited to, the above described system in Berry.

The above references to the background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the impact rotor as disclosed herein.

SUMMARY OF THE DISCLOSURE In one aspect there is disclosed an impact rotor for a material processing system and capable of rotating about a rotation axis comprising a base plate; a first circular array of hollow impact bars disposed about the rotation axis, wherein one end of each impact member is coupled to the base plate; each impact bar is provided with a continuous outer surface being coated with hard facing; and a first support ring coupled to an opposite end of each impact bar.

In a second aspect there is disclosed an impact rotor for a material processing system capable of rotating about a rotation axis comprising: a base plate; a first circular array of impact bars disposed about the rotation axis, each impact bar being made of a plastics material; a first support ring; and for each impact bar, one or more mechanical fasteners arranged to couple the impact member to the base plate and the first support ring.

In third aspect there is disclosed a material processing system comprising: an impact rotor according to the first or second aspect; an impact mechanism connected to the base plate, the impact mechanism centred on the axis and having one or more radially extending hammers or flails; and a first stator surrounding the axis and located between the axis and the first circular array, the first stator comprising one or more first surface portions and a plurality of holes or gaps in or between the surface; and wherein material entering the material processing system is impacted by the impact mechanism and accelerated in a radial outward direction onto the first stator wherein the material is impacted on the first surface portions or passes through 1 of the holes or gaps

BRIEF DESCRIPTION OF THE DRAWINGS Notwithstanding any other forms which may fall within the scope of the mill as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the covering drawings in which:

Figure 1 is a perspective view of one embodiment of the disclosed impact rotor;

Figure 2 is a side view of the impact rotor shown in Figure 1;

Figure 3 is a plan view of the impact rotor shown in Figure 1;

Figure 4 is a perspective view of a second embodiment of the disclosed impact rotor;

Figure 5 is a representation of a portion of a material processing system incorporating embodiments of the disclosed impact rotor, a central impact mechanism, and a stator arrangement;

Figure 6 is a radial section view of the material processing system shown in Figure 5; and

Figure 7 is a representation of the stator arrangement incorporated in the material processing system.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS Referring to Figs 1-3 a first embodiment of the disclosed impact rotor 10 which is suitable for use in for a material processing system, such as, but not limited to a multistage hammer mill as exemplified in the above referenced international publication WO 2018/053600 (Berry), the contents of which are incorporated herein by way of reference. The impact rotor 10 is capable of rotating about a rotation axis 12. The impact rotor comprises a base plate 14 and a first circular array 16a of hollow impact bars 18 which are disposed about the rotation axis 12. One end 20 of each impact bar 18 is coupled to the base plate 14. Each impact member 18 has a continuous outer surface 22 which is coated with hard facing. The impact rotor 10 also has a first support ring 24a that is coupled to an opposite end 26 of each impact bar 18.

In one embodiment the impact bars 18 can be made from a mild steel tube hard-faced using a laser process with a tungsten carbide cladding.

The base plate 14 and the first ring 24 are also made of metal. This allows the impact bars 18 to be welded to the base plate 14 and 24.

The impact bars 18 may have a variety of cross-sectional shapes including, for example, and not limited to, square or circular. A further benefit is derived where the cross-sectional shape is symmetrical about a plane P (shown in Fig 3) that passes through a geometric centre of the impact 18 and the rotation axis 12. This benefit arises when a material processing system (such as a multistage hammer mill of a type described in WO 2018/053600) incorporates two counter rotating and adjacent impact rotors 10. As will be understood by those skilled in the art, when a processing system has a rotating impact rotor, the leading edge with reference to the direction of rotation goes substantially greater wear than the trailing edge. When there are two counter rotating impact rotors, their respective worn leading edges are on opposite sides of the impact bars, as are their respective non, or less, worn trailing edges. So by swapping the two impact rotors so that they are rotated in direction to that previously endured, the less worn trailing edges now become the leading edges. This effectively extends the working life of the impact rotor.

Alternately the benefits of this extended life may be realised by the use of a serpentine belt, and associated idlers and pulleys to reverse the direction of rotation of the impact rotors 10.

This embodiment of the impact rotor 10 also includes a second circular array 16b of hollow impact bars 18 disposed about the rotation axis 12 and co-centric with the first circular array 16a. One end 20 of each impact bar 18 in the second array 16b is coupled to the base plate 14. Each impact member 18 has a continuous outer surface 22 which is coated with hard facing the same as for the first circular array 16a. A second support ring 24b is coupled to an opposite end 26 of each of the second array 16b impact bars 18.

The end 20 of the impact bars 18 in the second array 16b are welded to the base plate 14. Similarly the opposite end 26 of the impact bars are awarded to the second support ribs 24b.

Owing to the hollow nature of the impact bars 18, the weight of the impact rotor 10 is significantly lighter to an equivalent impact rotor with solid impact bars. By way of comparison with the impact rotors used in the commercially available mill described in WO 2018/053600, an embodiment of the disclosed impact rotor 10 may weigh up to between about 55% less. More specifically an embodiment of the disclosed impact rotor10 having 25 mm square section hollow bars 18 weighs approximately 24 kg compared with, about 43 kg for the impact rotor in aforementioned commercially available. The reduction in weight reduces the inertia of the impact rotor 10 thereby reducing the load on an associated drive system at start-up. The weight reduction also makes it easier to handle the material processing system during installation and maintenance, as well as reducing the mechanical weight load on the combine in his suspension system.

Figure 4 illustrates an alternate embodiment of the impact rotor, designated as 1Op, which is of a generally similar configuration to that of the first embodiment but in which impact bars 18p are made from a hard plastics material, such as but not limited to ultra-high-molecular-weight polyethylene; high density polyethylene; and polyetheretherketone. There is an inner and an outer array 16a, 16b of the impact bars 18p. The impact bars 18p are coupled one end to the base plate 14. Each array has an associated support ring 24a, 24b to which the bars 18p are coupled. The base plate 14 and the support rings 24 in this embodiment an age of a metal or metal alloy.

Mechanical fasteners, such as bolts 30 are used to connect the bars 18p to the base plate 14 and the respective support rings 24. In one embodiment a single mechanical fasteners/bolts 30 may be used to couple a corresponding impact 18p its support ring 24 and the base plate 14. In this arrangement the bolt 30 extends wholly through the corresponding impact bar 18p.The impact bars 18p can be formed with the same cross-sectional shape as described in relation to the impact bars 18 of the first embodiment.

The impact rotor 1Op provides the same benefits in terms of its lightweight and lower inertia as the first embodiment of impact rotor 10.

The base plate 14 of either embodiment of impact rotor 10, 1Op may be provided with one or more scrapers 39. The scrapers 39 located on an upper face of the base plate 14 and radially outside of an outer most circular array of impact bars 18. Moreover, the base plate 14 is provided with radially outward extending lugs on which respective scrapers 39 are coupled.

Figures 5-7 illustrate embodiments of a stator arrangement may be used with embodiments of the impact rotor 10, 1Ob to construct a material processing system such as a multistage hammer mill.

Figures 5 and 6 illustrate an impact mechanism 40 connected to the base plate 14. The impact mechanism 40 centred on the rotation 12 axis and has one or more radially extending hammers or flails 42. The material processing system includes a first stator 44 that surrounds the axisl2 and is located between the axis and the first circular array 16a of impact bars 18. The first stator comprising first surface portions 46 and a plurality of holes or gaps 18 in or between the first surface portions 46. In this embodiment the first stator 44a is in the form of a mesh, or perforated plate 48. The solid or material portions of the mesh plate form the first surface portions 46. The holes or gaps in the mesh or perforated plate 48 are the holes or gaps in between the first surface portions 46.

A plate 50 with a central opening 52 lies over the impact rotor 10 and the first stator 44a. A central opening 52 constitutes an inlet for material being processed. The material that enters the material processing system through the opening 52 is impacted by the impact mechanism 40 and accelerated in a radial outward direction onto the first stator 44. This material is impacted on the first surface portions 46 resulting in fragmentation, crushing or milling; or pass through the holes or gaps in the stator 44a.

In this embodiment is a second stator 44b, and third stator 44c. Each of the stators 44b and 44c are of the same or similar construction, configuration and function as the first stator 44a. However, the diameters of the second and third stators are progressively larger. Also optionally the holes or gaps in the stators may be formed to be progressively smaller with increasing distance from the axis 18.

The second stator 44b surrounds the first array 16a of the impact mechanism 10. The third stator 44c surrounds the second array 16b of the impact mechanism 10. The impact rotor 10 together with the impact mechanism 40 are rotated together as a single unit. Material entering the material processing system through the opening 52 is thus subjected to multiple impacts as it travels to an outlet (not shown) which is formed in a housing (also not shown) that surrounds the impact rotor and stator arrangement. When this material is chaff containing weed seeds the weed seeds are devitalised due to being fragmented, crushed or milled.

The scraper 39 on the impact mechanism 10 assists in drawing material through the outermost stator/screen. This should be distinguished from the provision of a scraper on an under surface which may have an adverse effect of drawing in air from below.

In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" and variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the mill and residue processing system as disclosed herein.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An impact rotor for a material processing system and capable of rotating about a rotation axis comprising: a base plate; a first circular array of hollow impact bars disposed about the rotation axis, wherein one end of each impact member is coupled to the base plate; each impact bar is provided with a continuous outer surface being coated with hard facing; and a first support ring coupled to an opposite end of each impact bar.

2. The impact rotor according to claim 1 wherein the one end of each impact bars welded to the base plate.

3. The impact rotor according to claim 1 or 2 wherein the opposite end of each impact bar is welded to the support ring.

4. The impact rotor according to any one of claims 1-3 comprising a second circular array of impact bars disposed about the rotation axis and co-centric with the first circular array, each impact bar of the second circular array comprising a hollow bar provided with a continuous outer surface and having one end coupled to the base plate; and a second support ring coupled to and oxygen end of each impact bar of the second circular array.

5. The impact rotor according to any one of claims 1-4 wherein at least some of the hollow bars have a square or circular cross-sectional shape.

6. An impact rotor for a material processing system capable of rotating about a rotation axis comprising: a base plate; a first circular array of impact bars disposed about the rotation axis, each impact bar being made of a plastics material; a first support ring; and for each impact bar, one or more mechanical fasteners arranged to couple the impact member to the base plate and the first support ring.

7. The impact rotor according to claim 6 wherein the one or more mechanical fasteners comprise at least one fastener that extends wholly through the impact bar and connects the first support ring to the base plate.

8. The impact rotor according to claim 6 or 7 wherein the base plate is made from a metal or metal alloy.

9. The impact rotor according to any one of claims 6-8 wherein the first support ring is made from a metal or metal alloy.

10. The impact rotor according to any one of claims 6-9 comprising: a second circular array of impact bars disposed about the rotation axis and co centric with the first circular array, each impact member of the second circular array being made of a plastics material; a second support ring coupled; and for each impact member of the second array, one or more mechanical fasteners arranged to couple the impact bars to the base plate and the second support ring.

11. The impact rotor according to claim 10 wherein the one or more mechanical fasteners comprise at least one fastener that extends wholly through at least one of the impact bars of the second array and connects the second support ring to the base plate.

12. The impact rotor according to any one of claims 1-11 comprising one or more scrapers supported on an upper side of the base plate and outside of an radially outermost circular array of impact bars.

13. A material processing system comprising: an impact rotor according to any one of claims 1-12; an impact mechanism connected to the base plate, the impact mechanism centred on the axis and having one or more radially extending hammers or flails; and a first stator surrounding the axis and located between the axis and the first circular array, the first stator comprising one or more first surface portions and a plurality of holes or gaps in or between the surface; and wherein material entering the material processing system is impacted by the impact mechanism and accelerated in a radial outward direction onto the first stator wherein the material is impacted on the first surface portions or passes through 1 of the holes or gaps.

14. The impact processing system according to claim 13 comprising a second stator surrounding the first circular array, the second stator comprising one or more second surface portions and a plurality of holes or gaps in or between the second surface portions, wherein material passing through the first stator and impacted by the by first array is accelerated in a radial outward direction onto the second stator wherein the material is impacted on the second surface portions or passes through one of the holes or gaps in between the third surface portions.

15. The impact processing system according to claim 14 comprising a third stator surrounding the second circular array, the third stator comprising one or more third surface portions and a plurality of holes or gaps in or between the third surface portions, wherein material passing through the second stator and impacted by the by second array is accelerated in a radial outward direction onto the third stator wherein the material is impacted on the third surface portions or passes through one of the holes or gaps in or between the third surface portions.

10 16a 16b 12 Aug 2021

24a

24b 2021221806

18

14 39

22 26 41 20 FIG 1 10

24a 18

39

41 FIG 2

P

24a 18

24b 22 2021221806

12

14

FIG 3

16a

10p Aug 2021

16b 24a

24b FIG 4 14 2021221806

30 18 40 18 52 40 42 50

42 14

44a 44c 48 44b FIG 5 44c 46

44a FIG 6 4 44b 8 44c

48

48 FIG 7