AU677615B2

AU677615B2 - Threshing of harvested grain

Info

Publication number: AU677615B2
Application number: AU53889/94A
Authority: AU
Inventors: Andrie Diederich Visagie
Original assignee: Modimp Ltd Pty
Current assignee: MODIMP Pty Ltd
Priority date: 1994-01-19
Filing date: 1994-01-19
Publication date: 1997-05-01
Anticipated expiration: 2014-01-19
Also published as: AU5388994A

Description

1- P/00/00 II Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

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ORIGINAL

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S Name of Applicant: MODIMP (PROPRIETARY) LIMITED Actual Inventor: ANDRIE DIIEDERICH VISAGIE Address for service in Australia: CARTER SMITH BEADLE 2 Railway Parade Camberwell Victoria 3124 Australia Invention Title: THRESHING OF HARVESTED GRAIN The following statement is a full description of this invention, including the best mnethod of performing it known to us 1997-02-26 09:03 CARTER SMITH BEADLE 61 3 98829854 P.04 2 This invention relates to the threshing of harvested grain. It relates more specifically to a method of threshing harvested grain and to harvcsting apparatuo.

It is envisaged that the invention will find particular application in the field of threshing of grain like maize (corn), wheat, beans, and the like.

In accordance with a first aspect of the invention, there is provided a method of threshing harvested grain in the form of ears, pods and the like, the method including: providing a threshing zone having a longitudinal threshing axis, having an inlet for the harvested grain at one longitudinal end thereof and an outlet for chaff at an opposed longitudinal end thereof, the threahing zone being bounded along a lower extremity thereof by means of a longitudinally 15 extending sieve, perforations of the sieve being selected to pass grain liberated during threshing with liLtle clearance, threshing means within Lhe threshing zone, winnowing volume outside the sieve which winnowing volume is bounded by means of a trough exLending generally longitudinally of the longitudinal threshing axis, which has a grain outlet at one end corresponding to Lhat end of the threshing zone having the inlet, and which has a chaff outlet at an opposed end corresponding to the end of the threshing 9:zone having the outlet, a fan aligned with the threshing zone and having an inlet covering the outlet of the threshing zone and being exposed to the chaff outlet of the winnowing volume; M4AWiP 1 #I4R41S.. J r6whY 101 1997-02-26 09:03 CARTER SMITH BEADLE 61 3 98829854 3 performing a threshing action on the harvested grain to liberate grain from chaff; operating the fan to cause a main air flow stream of predetermined force or intensity to move longitudinally through the threshing zone, the force or intensity of the main air flow stream being predetermined generally such as to carry chaff (of relatively low density) out of the threshing zone via that portion of the inlet of the fan covering the outlet of the threshing zone and to allow liberated grain ojf relatively high density) to fall onto the sieve and via the perforations into the winnowing volume, and to cause an auxiliary air flow stream of predetermined force or intensity to flow through the winnowing volume, the force or intensity being predetermined such as to carry chaff (of relatively low density) out of said winnowing volume via that portion of the fan inlet expoised to the winnowing volume, and such as not to carry liberated grain (of relatively high density) away, and to cause the main air flow stream and the chaff carried therein and the auxiliary air flow stream and the chaff carried therein to exit via an outlet S 20 of the fan.

The method may include arranging the threshing zone at an inclined attitude along a threshing axis, the sieve being correspondingly inclined and concentric to the threshing axis S 2 and the air flow stream being directed longitudinally of the 25 threshing axis. The axis may be inclined at at least about 200, conveniently at at least about 30° and preferably at about 450.

A/T O: -k -V jJO&C 1997-02-26 09:04 CARTER SMITH BEADLE 61 3 98829854 P.06 4 The method may include transporting the harvested grain into the threshing zone in a direction longitudinally of the threshing axis. Such transporting may be effected by means of a screw conveyor or auger, which is co-axial with the threshing axis.

The threshing action may be performed by means of beater bars mounted for rotation about an axis which is co-axial with the threshing axis.

Similarly, the air flow stream may be generated by means of a fan co-axial with the threshing axis.

Advantageously, the method may then include mounting the screw conveyor or auger, beater bars and fan on a common shaft or axle co-axial with the threshing axis and driving the screw conveyor or auger, beater bars and fan by means of said common o k 15 shaft or axle.

By way of development, there is provided a composite method of threshing harvested grain in the form of ears, pods, and the like, the composite method including a primary method step as described above, and a secondary method step, performed 20 subsequent to and and in series with the primary method step, the secondary method step including agitating or stirring liberated grain obtained from the primary method step in a cleaning zone which is bounded, at least along a lower extremity thereof, by a sieve, and causing an air flow stream of predetermined force or intesity to move through the cleaning zone, perforations of the sieve being selected to pass R- MA, M 3>Tdn,., J,7 I *L1 9 yt 1997-02-26 09:04 CARTER SMITH BEADLE 61 3 98829854 P.07 cleaned grain with little clearance, the force or intensity of the air flow stream being predetermined generally such as to carry chaff (of relative low density) out of the cleaning zone and to allow cleaned grain (of relatively high density) to fall onto the sieve.

The secondary method step may be performed generally adjacent the primary method step, and in generally similar manner.

Advantageously, liberated grain obtained from the primary method step may be transported under gravity to an inlet of apparatus performing the secondary method step.

In accordance with a second aspect of the invention, there is provided threshing apparatus suitable for use in threshing 9**U harvested grain in the form of ears, pods and the like, the 15 threshing apparatus including: casing means defining a threshing zone having a longitudinal threshing axis, having an inlet for the harvested grain at one longitudinal end thereof and an outlet for chaff at an opposed longitudinal end thereof; cot

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20 a longitudinally extending sieve bounding the threshing zone along a lower extremity thereof, perforations of the sieve being selected to pass grain liberated during threshing with little clearance; transport means arranged to transport the harvested grain via the inleL for the harvested grain into the threshing zone; threshing means within the threshing zone; b^ r J 1997-02-26 09:05 CARTER SMITH B3EADLE 61 3 98829851 P.O8 a winnowing volume outside the sieve which winnowing volume is bounded by means of a trough extending generally longitudinally, which has a grain outlet at one end corresponding to the end of the threshing zone having the inlet, and which has a chaf f outlet at an opposed end corresponding to the end of the threshing zone having the outlet; a fan aligned with the threshing zone and having an inlet covering the outlet of the threshing zone and being exposed to the chaff outlet of the winnowing volume, the fan being arranged, in use, to cause a main air f low stream of predetermined force or inLensiLy Lo move longitudinally through the threshing zone, the force or intensity of the main air flow stream being predetermined generally such as to carry chaff (of relatively low density) out of the threshing zone via that porLion of Lhe inlet of the fan covering the outlet of the threshing zone and to allow liberated grain (of relatively high density) to fall onto the sieve and via the perforations into winnowing volume, and to cause an auxiliary air flow stream 20 of predetermined force or intensity to flow through the winnowing volume, the force or intensity being predetermined such as to carry chaff (o1 relatively low density) out of said winnowing volume via that portion of the fan inlet exposed Lo the winnowing volume, and such as not to carry liberated grain (of relatively high density) away, and LO cause the main air flow sLream and the chaff carried therein and the auxiliary air flow stream and the chaff carried therein to exit via an outlet of the fan.

1997-02-26 09:05 CARTER SMITH BEADLE 61 3 90829854 P.09 The threshing zone may be generally round cylindrical, hav~ing a threshing axis. The threshing axis may be inclined at an angel of at least 200 from the horizontal, advantageously at least about 300, preferably about 45". The sieve may be correspondingly arcuate and may be arranged concentrically of the threshing axis.

The Threshing means may include beater bars arranged for rotation about a rotation axis which coincides with the threshing axis.

The transport means may be arranged to transport the harvested grain into the threshing zone in a direction 1 PANry 1007 MAW:PP:Nl4148.t.KS 6 longitudinal of the threshing axis. The transport means may include a screw conveyor or auger which is arranged co-axially with the threshing axis.

Similarly, the air flow stream generating means may be arranged to cause the air flow stream to move longitudinally of the threshing axis. The air flow stream generating means may be in the form of a fan co-axial with the threshing axis.

~Then, advantageously, the beater bars, screw conveyor or auger, and fan may be mounted on a common shaft or axle coaxial with the threshing axis and may be arranged to be driven in use by said common shaft or axle.

By way of development, there is provided composite Sthreshing apparatus comprising primary apparatus as described S. above, and secondary apparatus in the form of cleaning apparatus comprising casing means defining a cleaning zone; a sieve bounding at least a lower extremity of the cleaning zone; transport means arranged to transport liberated grain obtained from the primary apparatus into the cleaning zone; agitating or stirring means aranged to agitate or stir the liberated grain in the cleaning zone; and air flow stream generating means arranged to move air in an air flow stream through the cleaning zone, 7 the arrangement being such that grain, cleaned during agitating or stirring, falls onto the sieve, perforations of the sieve being selected to pass such cleaned grain with little clearance, and such that chaff is carried in the air flow stream out of the cleaing zone.

The secondary apparatus may be arranged adjacent to and parallel with the primary apparatus.

9 *9 *Advantageously, the transport means of the secondary apparatus may be arranged to transport the liberated grain under P" gravity.

The invention is now described by way of example with eeoc ""reference to the accompanying diagrammatic drawings. In the drawings Figure 1 shows, in axial section, threshing apparatus in accordance with the invention; and Figure 2 shows a section taken at II-II in Figure 1.

With reference to the drawings, threshing apparatus in accordance with the invention is generally indicated by reference numeral 10. The threshing apparatus is composite threshing apparatus comprising first apparatus in the form of threshing apparatus generally indicated by reference numeral 12 and second apparatus in the form of cleaning apparatus generally indicated by reference numeral 112. The first and second apparatus are arranged to perform successive steps in the method of the invention i.e. in series. The second apparatus is arranged generally below the first apparatus.

The first, threshing, apparatus 12 comprises a generally round cylindrical casing generally indicated by reference numeral 14 and defining a threshing zone generally indicated by reference numeral 16 about a threshing axis 20. The threshing axis 20 is arranged, in this embodiment, at an angle S 21 which is between about 300 and about 450 from the horizontal.

The first, threshing, apparatus 12 comprises threshing jje': means 18 operatively provided within the threshing zone 16.

Transport means 22, which is in the form of a screw eo conveyor or auger is arranged to transport harvested crop in the forms of ears, pods, or the like from a hopper 28 obliquely .eeeei upwardly into the threshing zone 16. The screw conveyor 22 is conveniently co-axial with the axis :e A boundary along a lower extremity of the threshing zone 16 is defined by means of an arcuate, trough-like sieve 24 having perforations 24.1. The sieve 24 is arranged concentrically with the axis At one end, which is an upper end in use, of the threshing zone 16, there is provided a fan 26, co-axially with the threshing axis 20, to generate an air flow stream from the hopper 28, through the threshing zone, and to exhaust it via 9 outlet conduiting 32. The fan 26 is of the centrifugal type and its inlet is thus on axis.

A common shaft or axle 30 acts as a tubular shaft over which flighting of the auger 22 is provided, and in series with the flighting, beater bars 18.1 of the threshing means are mounted on the shaft 30 to extend radially and longitudinally.

Also the fan 26 is mounted on the shaft a 0" Underneath the sieve 24, and concentrically with the axis 20, there is provided a trough 34 which is, at its lower Send, open as indicated at 36. The open end 36 corresponds to the hopper 28 and leads into transport means of the second threshing apparatus 112.

go Air inlet openings 35, which are out of the plane of the section of Figure 1 and which can be perceived from Figure 2, allow air to be drawn via the trough 34 as shown at 37 into the fan 26. The inlet opening of the fan 26 is sufficiently large to have an influence outside the threshing zone 16. A volute for the fan 26 is formed partially by a baffle 27 at an upper end of the trough 34.

It is to be appreciated that, because the sieve 24 is merely arcuate and not circular, the air flow stream 37 moves in a relatively narrow channel, thus making it more effective, alternatively requiring less air to be moved.

In use, harvested crops in the form of ears, pods, or the like fall under gravity into the hopper 28 to be transported obliquely upwardly as indicated at 44 into the threshing zone 16 by means of the transport means 22. In the threshing zone 16, the ears, pods or the like are threshed to liberate grain from chaff.

The chaff in the threshing zone 16 is carried by the flow stream through the fan 26 to be exhausted via the conduiting 32 as indicated at 48.

The grain falls under gravity and under centrifugal force through the air flow stream onto the sieve 24. The apertures 24.1 are selected to pass liberated grain with clearance. Thus, liberated grain, with an amount of relatively small pieces of chaff, fall into the trough 34 as indicated by reference numeral 46.

44* The small pieces of chaff are carried by the flow stream 37 via the fan 26 into the outlet 32.

The liberated grain 46 slides along the trough 34 via the open end 36 onto the transport means 122 of the second, cleaning apparatus 112.

The second, cleaning, apparatus 112 is similar to the first, threshi'ng, apparatus 12 and is not again described. Like referunce numerals refer to like components or features.

11 Reference numeral 118 indicates stirring bars or agitating bars in place of the beater bars. 18.1.

Cleaned grain 146 is discharged from the threshing apparatus 10 via an outlet 136 where it is collected. Chaff is exhausted via the conduiting 32 and 132.

The Applicant believes that, in many applications, threshing by means of the first, threshing, apparatus 12 will provide adequately cleaned grain and that a second step, which 6 9.

will merely be a cleaning step, will not be required. Thus, in those applications, grain will be collected from the open end 36.

It is a first advantage that grain and chaff are separated already in the threshing zone 16. This is conducive to simplicity of design and effectiveness in operation.

Transport of the liberated grain and chaff is facilitated and the threshing apparatus can be provided less expensively than comparable threshing apparatus of which the Applicant is aware.

It is further an advantage that the sieve 24 is stationary as it is operated by means of gravity and centrifugal forces, operating on the liberated grain.

It is a further advantage that the sieve through which the liberated grain is passed is merely arcuate and not fully cylindrical. Provision of an arcuate or, in this case, semicylindrical sieve is adequate and allows a saving in cost.

Claims

1997-02-26 09:05 CA~RTER SMITH BEADLE 5 ES~*' 61 3 99029U54 12 The claims defining the invention are as follows: 1. A method of threshing harvested grain in the f orm of ears, pods and the like, the method including: providing a threshing zone having a longitudinal threshing axis, having an inlet for the harveated grain at one longitudinal end thereof and an outlet for chaff at an opposed longitudinal end thereef, the threshing zone being bounded along a lower extremity thereof by means of a longitudinally extendin.- jieve, perforations of the sieve being selected to pass grain liberated during threshing with little clearance, threshing means within the threshing zone, a winnowing volume outside the sieve which winnowing volume is bounded by means of a trough extending generally longitudinally of the longitudinal threshing axis, which has a grain outlet at one end corresponding to that end of the threshing zone having the inlet, and which has a chaff outlet at an opposed end corresponding to the end of the threshing having the outlet, a fan aligned with the threshing zone and having an inlet covering thle outlet of the threshing zone and being exposed to the chaff outlet of the winnowing volume; performing a threshing action on the harvested grain to liberate grain from chaff; operating the fan to cause a main air flow stream of predetermined force or intensity to move longitudinally through the threshing zone, the force or intensity of the main air flow stream being predetermined generally such as to carry chaff (of relatively low density) out of the threshing zone via that portion of the inlet of the fan covering the outlet of the threshing zone and to allow liberated grain (of relatively high MAWTI~MOA.SI Fghkary M7 19W-Od-;G 06 (AMRTLR bm)T MAW [Jb i 3 90)90[54 P.111 13 density) to fall onto the sieve and via the perforations into the winnowing volume, and to cause an auxiliary air flow stream~ of predetermined force or intensity to flow through the winnowing volume, the force or intensity being predetermined such as to carry chaff (of relatively low density) out of said winnowing volume via that portion of the fan inlet exposed to the winnowing volume, and such as not to carry liberated grain (of relatively high density) away, and to cause the main air flow stream a-ad the chaff carried therein and the auxiliary air flow stream and the chaff carried therein- to exit via an outlet of the fan.

2. A method as claimed inl claim 1 which includes arranging the longitudinal threshinS axis at an inclined attitude at a predetermined angle to the horizontal, the angle to the horizontal being selected such as to cause liberated grain to slide under gravity against the auxiliary air flow stream along the trough to the grain outlet.

3. A method as claimed in claim 1 or claim 2 which includes providing a grain cleaning device for cleaning the S* 20 grain from the grain outlet, the grain cleaning device including: a cleaning zone having a longitudinal cleaning as parallel to the longitudinal Lhreshing axis, having an inlet for the liberated grain at urnc longitudinal end thereof arranged generally underneath the grain outlet, having a chaff outlet opposite to the inlet, and being bounded along a lower extremity thereof by means of a longitudinally extending cleaning sieve, perforations of the cleaning sieve being selected to pass cleaned gra-in with little clearance; transport means for transporting liberated grain from the MAkW:I'VIqIt.ISI 2S Nhm" 1007 1997-02-26 09:06 CARTER SMITH BEADLE 61 3 98829854 P.12 14 grain outlet longitudinally into the cleaning zone; agitating or stirring means in the cleaning zone; and a fan aligned with the cleaning zone and having an inlet exposed to the chaff outlet, the method further including: operating the transport means to transport liberated grain obtained from the grain outlet into the cleaning zone; operating the agitating or stirring means to agitate or stir the grain obtained from the grain outlet; and operating the cleaning fan to cause a cleaning air flow stream of predetermined force or intensity to move through the cleaning zone, the force or intensity being predetermined generally such as to carry chaff (of relatively low density) out of the cleaning zone and to allow cleaned grain (of relatively high density) to fall onto and through the cleaning sieve.

4. Threshing apparatus suitable for use in threshing harvested grain in the form of ears, pods and the like, the threshing apparatus including: 20 casing means defining a threshing zone having a longitudinal threshing axis, having an inlet for the harvested grain at one longitudinal end thereof and an outlet for chaff at an opposed longitudinal end thereof; a longitudinally extending sieve bounding the 25 threshing zone along a lower extremity thereof, perforations of the sieve being selected Lo pass grain liberated during threshing with little clearande; transport means arranged to transport the harvested grain via the inlet for the harvested grain into the threshing zone; threshing means within the threshing zone; MAW:PPI'(1448.PSI 2 rdJminy 1997 1997-02-26 09:07 CFARTER SMITH &BERL)LE 61 3 98829854 P113 a winnowing volume outside the sieve which winnowing volume is bounded by means of a trough extending generally longitudinally, which has a grain outlet at one end corresponding to the end of the Lhreshinq zone having the inlet, and which has a chaff outlet at an oppoged end corresponding to the end of the threshing zone having the outlet; a fan aligned with the threshing zone and having an inlet covering the outlet of the threshing zone and being exposed to the chaff outlet of the winnowinig volume, the fan being arranged, in use, to cause a main air flow stream of predetermined force or intensity to move longitudinally through the threshing zone, the force or intensity of the main air flow stream being predetermined generally such as to carry chaff (of relatively low density) out of the threshing zone via that portion of the inlet of the fan covering the outlet of the :threshing zone and to allow liberated grain (of relatively high :density) to fall onto the sieve and via the perforations into the winnowing volume, and to cause an auxiliary air flow stream of predetermined f orce or intensity to f low through the winnowing volume, the force or intensity being predetermined such as to carry chaft i(of relatively low density) out of said winnowing volume via that portion of the fan inlet exposed to the winnowing volume, and such as not to carry liberated grain :25 (of relatively high density) away, arid to cause the main air flow stream anid the chaft Icarried therein and the auxiliary air f low stream and t*Le chaff carried therein to exit via an outlet of the fan. Threshing apparatus as clgimed in claim 4, in which the longitudinal threshing axis is arranged at an inclined MAW1111.0 142 4 PAS I 25 Fc*bluary 1097 7-2-26 09:R0 CRRTER SMITH BERDLE bi 3 9 y29954 P.14 16 attitude at a predetermined angle to the horizontal, the angle to the horizontal being selected such as to cause liberated grain to slide under gravity against the auxiliary air flow stream along the trough to the grain outlet. 6. Threshing apparatus as claimed in claim 4 or claim which includes a grain cleaning device for cleaning the grain from the grain outlet, the grain cleaning device including: casing means defining a cleaning zone having a longitudinal cleaning axis parallel to the longitudinal threshing axis, having an inlet for the liberated grain at one longitudinal end thereof arranged generally underneath the grain outlet, and having a chaff outlet opposite to the inlet; a longitudinally extending cleaning sieve bounding a lower extremity of the cleaning zone, perforations of the cleaning 15 sieve being selected to pass cleaned grain with little 9. o clearance; a. transport means for transporting liberated grain from the grain outlet longitudinally into the cleaning zone; *agitating or stirring means in the cleaning zone; and a cleaning fan aligned with the cleaning zone and having an inlet exposed to the chaff outlet, the cleaning fan being 'S arranged to cause a cleaning air flow stream of predetermined force or intensity to move through the cleaning zone, the force or intensity being predetermined generally such as to carry 25 chaff (of relatively low density) out of the cleaning zone and 9. to allow cleaned grain (of relatively high density) to fall onto and through the cleaning sieve. 7. A method of threshing harvested grain according to any one of claims 1 to 3 substantially as hereinbefore described. MAW:PP:MNl14|41.u 25 embouiry 1997 1997-02-26 09:08 CARTER SMITH BEADLE 61 3 90029654 P.1is 8. A threshing apparatus according to any one of claims 4 to 6 substantially as hereinbefore described. DATED; 25 February 1997 CARTER SMITH~ BEADLE Patent ALtorneys for the Ap7-icant: MoDIisP (PROPRIETAR~Y) LIMITED C 4* C C C C C.. C C. C C C C. C C C C. C C CC C. C MAWPPhd41S.RSI2 ImryIV 25 Pebruiry 1991 ABSTRACT A threshing apparatus (l0) has an inclined threshing zone (6) bounded below by a sieve Harvested grain (40) is transported longitudinally into the zone (16)by means of an auger(22 Beater bars (18.1) perform a threshing action on the grain. A fan (26) moves air longitudinally through the zone (16)at an intensity such that liberated grain of relatively high density falls on the sieve and chaff of relatively low density is expelled via the fan The auger, beater bars and fan are all mounted on and driven by a common shaft Cleaning apparatus, similar in construction and operation, is arranged adjacent to and parallel to the threshing apparatus. The cleaning apparatus cleans the *r g liberated grain of remaining chaff. 0 *o.0 a