WO2000067554A1

WO2000067554A1 - Harvesting and separating apparatus

Info

Publication number: WO2000067554A1
Application number: PCT/GB2000/001635
Authority: WO
Inventors: Cedric Sharpe
Original assignee: Pryde Foundation
Priority date: 1999-05-06
Filing date: 2000-04-27
Publication date: 2000-11-16
Also published as: GB9910334D0; GB9917968D0; GB2335837A; TR200103486T2; CN1239067C; AU4586400A; GB2335837B; GB2341074A; GB2341074B; CN1371242A

Abstract

A whole crop harvesting and/or separating apparatus (1) for use with grain or seed bearing crops such as wheat, barley, pulses and the like. The apparatus comprises a first rotor (2) and concave (4) and a second rotor (6) and concave (8) arranged so as to define a substantially S-shaped path for a crop in use of the apparatus to pass along. The first (2) and second (6) rotors are driven in opposite rotational directions. The first concave (4) comprising a first threshing portion (10) having a plurality of radially extending crop engaging bars (12) spaced apart in the direction of rotation of the first rotor (2) for threshing, vigorously, of a crop in use of the apparatus. The second portion (16) of the first concave (4) and the second concave (8) comprise a plurality of spaced apart crop rubbing bars (18) inclined with respect to a radial direction. These crop rubbing bars (18) are formed and arranged with the first (2) and second (6) rotors so as to convey the stalk portion of a crop in use of the apparatus along the S-shaped path in a substantially non-stalk breaking manner whereby a maximum of 'long' straw passes around the concave path uncut. A straw breaking chamber (22) or baler may also be provided for the further processing of straw exiting the second concave. A multi-use wheeled undercarriage is provided with onboard hydraulic drive raising/lowering means.

Description

HARVESTING AND SEPARATING APPARATUS

The present invention relates to the harvesting and separating of crops where the process calls for cutting, (or retrieval of previously cut) crops of a stalk like nature, and the further need to thresh and to separate seed from stalk. The invention relates also to a wheeled undercarriage suitable for use with said harvesting and separating apparatus and which is suitable for multiple uses.

In the developed world, in the harvesting of wheat, barley and the like it is known to use a combine harvester which cuts a crop, threshes and separates the seed or grain from the stalk, separates further the seed from the straw on a straw walker and then cleans the grain and returns the straw in a more or less uncut and unbroken form onto the ground. For the straw to be harvested for subsequent use it has to be collected, and further processed, which requires separate machinery.

Whilst such combine harvesters have been developed to meet harvesting requirements in Western Europe or in North America their use, economically, physically and socially in the developing world make them not entirely suitable or at all practicable for use in harvesting crops grown in the developing countries of North Africa, Middle East and the Indian Sub Continent. In such areas small farms with small fields are common and crops such a wheat, barley and other pulse crops such as beans, gram and lentils and cereal crops such as sorghum are grown as much for the straw or stalk as for the grain, pulse or cereal produced. Seed or grain bearing stalk as used in herein refers to seeds or to grain proper and embraces also pulses. Traditionally in such countries the crop would be cut by a sickle and threshed by treading but in recent years such processes have become mechanised and threshing is undertaken by relatively simple and locally produced stationary threshers which thresh and separate the grain or crop from the straw and separates the grain into bags or other suitable containers and which allow for the straw to be collected so that it may be used for feed stuffs for livestock. In order though for such straw to be palatable for livestock the straw must be finely broken up into separate discrete portions so that these portions have no sharp edges. Sharp edges on straw/stalk can occur when it is cut or chopped. For the avoidance of doubt the term straw breaking as used herein is intended to have the meaning known to those skilled in the art i.e. that of separating a length of stalk into a plurality of discrete portions .

In the early 1960 's Massey Ferguson (Great Britain) Limited devised a threshing mechanism specially intended for use with combine harvesters comprising essentially two units each of which consisted of a drum and associated concave counterpart which were superimposed one above the other in a vertical ' S' shape so as to thresh a cut crop successively in each unit. This invention was the subject of French Patent publication no. 1226283. Although this system was intended for use with a combine harvester it was never adopted. Subsequently the ^λS' shape arrangement was used as the basis for United Kingdom patent no. GB 2160753 (in the name of BTG International Limited by inventors A.A. Metianu and I.M. Johnson) . The BTG patent teaches of a whole crop harvesting and separating apparatus which has first and second stalk breaking threshing rotors arranged in a ' S' shaped configuration and a plurality of closely spaced together crop engaging bars. Further disclosure regarding that invention is given in Paper no. 87- 5055 as presented to the 1987 summer meeting of the American Society of Agricultural Engineers by A.A. Metianu.

A particular disadvantage with the harvester disclosed in BTG and by Metianu is that the first and second rotors provide a very vigorous threshing and separating and the first and second rotors are specifically formed and arranged so as to perform a "stalk breaking process" in the sense of separating a cut stalk into a plurality of discrete portions. It has been found that undertaking the stalk breaking process simultaneously with grain separation process results in such harvester apparatus facing difficulty in subsequent cleaning of the grain into an acceptable quality to farmers by virtue of the added small broken straw content. Moreover such small broken straw portions mixed with the grain fall through between the crop engaging bars creating difficulties in subsequent grain cleaning operations. In this respect it will be noted that the BTG design does not employ circumferentially extending and positioned concave wires of the type used in a conventional combine harvester threshing concave. Instead to achieve the desired straw breaking BTG utilizes crop engaging bars which are arranged quite closely, specifically 30mm or less apart .

Thus whilst the relatively simple vertical 'S' shaped arrangement of threshing mechanism has been known for many years it has not yet realised the efficiencies claimed for such apparatus . Moreover it has been found that breaking the straw, in the sense of separating it into a plurality of discrete portions as it passes around the concaves, results in straw which has sharp edges and which is not palatable as foodstuff for livestock and not acceptable to farmers. It is an object of the present invention to avoid or minimise one or more of the foregoing disadvantages .

The present invention provides a whole crop harvesting and/or separating apparatus for use with grain or seed bearing crops as hereinbefore defined which apparatus comprises a first rotor and concave and a second rotor and concave ; drive means for driving said first and second rotors in opposite rotational directions to one another; said first and second rotors and said respective concaves being formed and arranged so as to define a substantially "S" shaped path for a crop in use of the apparatus to pass along; said first concave comprising a first threshing portion having a plurality of radially extending crop engaging bars spaced apart in the direction of rotation of the first rotor for threshing of a crop in use of the apparatus; characterised in that a second portion of said first concave following said first threshing portion thereof and said second concave comprises a plurality of spaced apart crop rubbing bars inclined with respect to a radial direction; said radially inclined crop rubbing bars being formed and arranged with said first and second rotors so as to convey the stalk portion of a said crop in use of the apparatus along said "S" shaped path in a substantially non- stalk breaking manner whereby a maximum of "long" straw passes around the concave path uncut .

Thus with an apparatus accordingly to the present invention grain or seed bearing crops may be threshed and grain or seed separated from the stalk and the stalk processed through said apparatus in a substantially whole "long" form so as it may be subsequently and finely broken up at a later stage so as to be palatable for livestock consumption or other uses. Preferably there is provided at the exit of the second rotor concave a straw breaking chamber formed and arranged with a rotor portion for pulverising straw into a form with no sharp or "cut" edges so as to be palatable for animal feedstock. The chamber has an outer wall portion having a plurality of holes formed and arranged so that only straw which is smaller than the size of the hole to pass through. Desirably there may be provided chamber wall portions having differing hole sizes such that different wall portions are used to process different crops or to provide straw of a minimum/maximum length according to a user's requirements.

Optionally and/or additionally there may be provided at the exit of the second rotor concave an additional third grain separating chamber comprising a third rotor and corresponding concave. At the exit of the third rotor concave straw may be simply discharged to the ground in a similar way to a conventional combine harvester and baled by a subsequent baling operation.

Alternatively instead of there being provided a said straw breaking chamber there may be provided a low density baling facility. Such a baling facility would be of generally known type and construction familiar to those skilled in the art such as a trusser.

Desirably straw is fed from the second rotor to the straw breaking chamber along a path lying substantially radially of the straw breaking chamber.

Preferably the apparatus is provided with a grain conveyor formed and arranged to convey separated grain or seed to a grain or seed bagging location. Desirably there may be provided a further grain separating means formed and arranged to separate grain or seed from any material other than grain (MOG) reaching the grain conveyor means . 5 Preferably there is provided at least one, desirably a plurality, of means of providing a stream of air to facilitate separation of grain from the MOG.

10 Preferably said drive means for said first and second rotors are formed and arranged such that said second rotor rotates approximately 33% faster that said first rotor. Preferably said first rotor has a rotational speed of 750 rpm and said second rotor a rotational speed of 1000 rpm.

15

Preferably said first and second concaves are provided with concave wires circumferentially extending there around. Preferably said concave wires are spaced apart by in the range of from 15 to 30mm, desirably 20 mm.

20

Preferably said first portion of said first concave and said radially extending crop engaging bars have a spacing of ° greater than 30mm and are formed and arranged so as to give an aggressive or vigorous threshing of crop in use of the

25 apparatus. Preferably said first portion of said first concave has an angular extend of from 90o to llOo desirably for example lOOo. Preferably there are provided in the range of from 14 to 16, desirably 15 crop engaging bars having a pitch of approximately 32mm at a radial angle of approximately

307.2o. The number of concave wires for such a threshing portion will of course depend on the width of the concave though preferably there is provided in the range of from 5 wires per 10cm of width. Preferably said first concave portion is mounted on an eccentric shaft so as to facilitate adjustment of the spacing between the rotor and the concave rub bars . Such an adjustment facility enables use of the apparatus with a variety of different crops.

Preferably said crop rubbing bars on said second portion of said first concave and around said second concave are formed and arranged merely to convey uncut and unbroken stalk there around and are formed and arranged so as to do so substantially without shearing or cutting, breaking or separating of straw stalk. This performs as a similar grain separation function to that on the straw walkers used on a conventional combine harvester. Desirably and conveniently this rubbing action of the crop rubbing bars on the crop serves to separate further any loose grain held within the broken straw passing around said concaves .

Preferably said crop rubbing bars have a backward inclination in the range of from 20 to 60o, desirably 40o, to the tangent of the periphery of the concave . Desirably said crop rubbing bars have a tip portion for cooperation with said respective rotors which is kinked back or further inclined in the range of from 40 to 80o, preferably 60o to the tangent of the periphery of the concave . Preferably said crop rubbing bars are spaced apart radially in the range of from 20 - 30 mm desirably 24mm.

Preferably said second portion of said first concave and said first and second portions of said second concave are of a substantially identical construction. In another respect the present invention relates to a mobile harvesting machine comprising a whole crop harvesting and/or separating apparatus provided with a cutting table; a crop gathering chamber; a crop elevator chamber; threshing and separating apparatus and grain conveying augers of generally known type and construction. Desirably said mobile harvesting apparatus according to another aspect of the invention is formed and arranged to be mounted to the three point linkage of a tractor. Alternatively for use as a mobile harvesting machine there is provided a chassis means provided with wheels, said chassis means being formed and arranged for connection to a tractor linkage or the like for drawing the harvesting machine across a field or the like. Desirably there is provided means in the form of, for example, hydraulic drive means for raising and lowering said chassis means and a said mobile harvesting machine supported thereby in use of the apparatus .

In yet another respect of the present invention relates to a wheeled undercarriage suitable for use with the harvesting and/or separating apparatus according to a first aspect of the invention which is formed and arranged for releasable connection to a towpoint on a tractor, for example, and provided with means, preferably hydraulic drive means, for raising and lowering said undercarriage with respect to the ground.

Such a wheeled undercarriage having built-in hydraulic raising and lowering means is particularly suitable for use in the developing countries where tractors and the like do not have powered three point linkages. Moreover such a wheeled undercarriage without said harvesting and/or separating apparatus may be used for many other applications, such as, for example, transport of harvested crop or supporting other machinery.

Further preferred features and advantages of the present invention will appear from the following detailed description given by way of an example of a preferred embodiment illustrated with reference to the accompanying drawings in which : - Fig. 1 is a side view of a harvester according to the invention;

Fig. 2a and b show in detail the first and second concaves of the apparatus shown in Fig. 1; and

Fig.3 shows a side view of a wheeled undercarriage for use with the harvester shown in Fig. 1

A whole crop harvesting apparatus, generally indicated by reference number 1, is shown in Fig. 1. The apparatus is for use with grain or seed bearing crops such as barley and wheat . The apparatus comprises a first rotor 2 and corresponding concave 4 and a second rotor 6 and corresponding concave 8 arranged one above each other . A drive mechanism drives the first 2 and second 6 rotors in opposite rotational directions to one another (as shown by arrows ^ΛA' and *B' respectively) so as to define a generally ^VS' shaped path for a crop in use of the apparatus 1 to pass along.

In more detail and with reference also to Fig. 2b the first concave 2 comprises a first threshing portion 10 having fifteen radially extending crop engaging bars 12 spaced apart by approximately 32mm in the direction of rotation of the first rotor 2. This first threshing portion 10 and the concave bars 12 provide a vigorous threshing action on the crop in use of the apparatus so as to sever seed or grain at its point of retention to a stalk portion, with the minimum amount of breakage to the straw or stalk. Separated seed is allowed to pass through the open areas of the concave between the concave bars 12 and peripherally extending concave wires 14 - (shown in broken line) . The concave bars 12 and concave wires 14 retain the straw in a substantially unbroken form so that it may continue its path onwards out of the threshing portion 10 of the first concave 4 into the second portion 16 of the first concave 4.

The arrangement of the concave bars 12 and wires 14 in the first portion 10 of the first concave 4 provide for the aggressive separation of the seed from the stalk to be confined and achieved as early as possible during passage of the crop through the apparatus in such a way that subsequent action over the remaining concave surfaces 16, 8 is merely to induce already freed seed to fall through the open areas of the concaves 8 while allowing the straw to continue progress around the concave paths with the minimum resistance consistent with adequate separation.

As the unbroken straw exits from the first portion 10 of the first concave 4 into the second portion 16 of the first concave 4 it encounters rubbing bars 18 inclined with respect to the radial direction of rotation of the rotor 2, which bars are angularly spaced apart at a pitch of approximately 24mm. The crop rubbing bars 18 cooperate with the rotating rotor so as to convey the uncut stalk portion of a crop in use of the apparatus along and around the * S' shaped path in a generally gentle fashion so as not to break or cut the stalk. This gentle rubbing action serves also to free any grain or seed not released in the first threshing portion 10. During the threshing operation, material other than grain (MOG) also passes through the first concave portion 10. This material requires also to be separated and removed. As the percentage of MOG present during the threshing operation increases with the breakage of the straw it will be apparent that reducing the breakage of straw during the threshing process reduces the percentage of MOG that has to be further separated and removed in a separate or additional grain cleaning operation.

Once unbroken straw exits from the second portion 20 of the second concave 8 and where unbroken stalk is required it may be passed into a baling facility or onto the ground for subsequent picking up and baling. In the presently described embodiment though the unbroken straw exits the second portion 20 of the second concave 8 and is introduced into a straw breaking chamber 22 provided with a number of hammer portions 24 mounted on a rotating rotor 26, which hammer portions 24 may be fixed or pivotally connected thereto, so as the straw entering the straw breaking chamber is pulverised by the action of the hammers on the straw. For the avoidance of doubt the arrangement of hammers is such that the uncut and unbroken straw is not cut by a shearing action or chopped as in the prior art but instead pulverised and shredded into generally discrete small portions so as to be palatable for animal feed.

In more detail and with reference again to Fig. 1 the mixture of separated grain and MOG which is passed through the concaves is conveyed by two augers, an upper one 28 and a lower one 30 serving each of the rotors 4, 6 respectively. This mixture of grain and MOG is then passed to a chain and paddle type elevator which passes the grain and MOG to a further auger 32 designed to distribute the material it conveys evenly across its length. Material falling from the distribution auger 32 falls through an airstream 34 generated by a variable speed fan 36. This variable speed fan draws air and any airborne MOG from the area around the shaker shoe portion 38 of the apparatus. This shaker shoe arrangement is of generally known type and construction and has an hole size and shape that may be varied to suit the crop in use of the apparatus .

A second variable speed fan 40 is provided to generate a stream 42 of air under the shaker shoe arrangement so that it has a separating effect on grain which is of a size capable of passing through the grading sieves. The air flow 42 prevents any lighter MOG which may be of a similar size to the grading sieves to be prevented from entering and passing through the sieves. Cleaned grain which passes through the sieves is directed to a conveying auger 44, under the effect of gravity on an inclined surface 46 and on the reciprocating action of the shaker shoe .

Light material such as chaff and any light and short broken straw portions which may have inadvertently been broken during the threshing and conveying stages is subject to the combined effect of the first 36 and second 40 fans and is drawn to the inlet of the first fan 36. Within this fan 36 the centrifugal action causes any such material to be concentrated peripherally. This material is then directed (indicated by arrow-C) under the action of the fan to the straw breaking chamber 22 where it may be processed together with unbroken straw and any excess air is exhausted (indicated by arrow ' D' in Fig. 1) . Any long straw or unbroken unthreshed heads or other material on the shaker sieves which is too large to pass through the holes and is too heavy to become airborne by the effect of the airstream is allowed to shake and to pass over the sieves and to fall under gravity onto the incoming crop elevator 48 so as to be recycled through the first and second concaves.

The harvester shown in Fig. 1 is designed as a mobile harvester to be drawn by a tractor. The harvester is mounted 49 on a wheeled undercarriage 50 (see also Fig. 3) and the harvester is provided with an offset cutting table 52 the crop side of the harvester 1.

The cutting table 52 is provided with a safety "break free" facility in the event of the cutting table meeting an obstruction. By providing a point 54 at the rear innermost vertical side of the cutting table, the table is maintained in its working position by virtue of a shear bolt arrangement at the front innermost vertical side attaching it to a mating arrangement on the harvester. This feature also enables the table to be opened by hinging, in addition to unbolting and removing in the event of their being a requirement to gain access to the crop elevating system.

The wheeled undercarriage 50 shown in Fig. 3 is designed to be fixed 49 by a drawbar 56 to a tractor (not shown) . The arrangement is such that it allows the harvester to be used on tractors with or without a hydraulic lift facility and there is provided a hand operated hydraulic power pack 58 for raising or lowering wheels between a raised transport position and a lowered operational/cutting position. The wheeled undercarriage 50 allows for the harvester to be carried at a cutting height down to approximately 50mm and in its transport position at a height sufficient to give adequate ground clearance in the region of 350mm. The variation in height is achieved by the use of a hydraulic ram or rams 62 acting on a lever system attached to a pivoting axle 64 at the rear of the undercarriage 50. The wheels 60 are attached to the axle 64 in a counter lever configuration such that the desired range and movement can be achieved. Hydraulic power may be taken from a suitably equipped tractor or, as shown in Fig. 3, from the separate hand operated hydraulic power pack 58.

Provision is made also for the adjustment of the fore and aft angular relationship of the harvester with respect to ground level. This is achieved by an adjustable top link 66 which allows the harvester to pivot on two lower linkage attachment points 68 on the undercarriage frame. This feature allows the folding of the cutting table through 18Oo. In this example the top link adjustment 66 is used to tilt the harvester with respect to the undercarriage to provide clearance while it passes over the right hand wheel 60. The harvester 1 may then be tilted back in the reverse direction to rest between the wheels. This facility allows the harvester to be transported in a position of reduced overall width. While in this position provision is made to attach a linkage between the wheels and the undercarriage frame to provide a fail-safe measure in the event of failure of the hydraulic system. The undercarriage also provides a rear towbar point 70 for drawing a trailer to collect and transport separated grain and processed straw.

Various modifications may be made to the above described embodiment without departing from the scope of the present invention as defined in the claims.

Claims

CLAI S

1. A whole crop harvesting and/or separating apparatus for use with grain or seed bearing crops as hereinbefore defined which apparatus comprises a first rotor and concave and a 5 second rotor and concave; drive means for driving said first and second rotors in opposite rotational directions to one another; said first and second rotors and said respective concaves being formed and arranged so as to define a substantially "S" shaped path for a crop in use of the

10 apparatus to pass along; said first concave comprising a first threshing portion having a plurality of radially extending crop engaging bars spaced apart in the direction of rotation of the first rotor for threshing of a crop in use of the apparatus; characterised in that a second portion of said

15 first concave following said first threshing portion thereof and said second concave comprises a plurality of spaced apart crop rubbing bars inclined with respect to a radial direction; said radially inclined crop rubbing bars being formed and arranged with said first and second rotors so as to convey the

20 stalk portion of a said crop in use of the apparatus along said "S" shaped path in a substantially non-stalk breaking manner whereby a maximum of "long" straw passes around the concave path uncut .

252. An apparatus as claimed in claim 1 where there is provided at the exit of the second rotor concave a straw breaking chamber formed and arranged with a rotor portion for pulverising straw into form with no sharp or cut edges.

303. An apparatus as claimed in claim 1 wherein there is provided at the exit of the second rotor concave a baling facility.

4. An apparatus as claimed in claim 1 wherein there is provided at the exit of the second rotor concave a third rotor and respective concave, said third rotor concave having a substantially similar construction to said second rotor concave .

5. An apparatus as claimed in claim 2 wherein straw is fed from the second rotor to the straw breaking chamber along a path lying substantially radially of the straw breaking chamber.

6. An apparatus as claimed in any one of claims 1 to 5 provided with a grain conveyor formed and arranged to convey separated grain or seed to a grain or seed bagging location.

7. An apparatus as claimed in any one of claims 1 to 6 provided with further grain separating means formed and arranged to separate grain or seed from any material other than grain (MOG) remaining in the processed grain.

8. An apparatus as claimed in any one of claims 1 to 7 wherein is provided at least one means of providing a stream of air to facilitate separation of grain from material other than grain.

9. An apparatus as claimed in any one of claims 1 to 8 wherein said drive means for said first and second rotors are formed and arranged such that said second rotor rotates 33% faster than said first rotor.

10. An apparatus as claimed in any one of claims 1 to 9 wherein said first and second concaves are provided with concave wires circumferentially extending there around.

11. An apparatus as claimed in any one of claims 1 to 10 wherein said radially extending crop engaging bars of said first portion of said first concave have a spacing of greater than 30mm.

12. An apparatus as claimed in any one of claims 1 to 11 wherein said first portion of said first concave has an angular extent of 100° and is provided with fifteen crop engaging bars having a pitch of 32mm at a radial angle of 7.2°.

13. An apparatus as claimed in any one of claims 1 to 12 wherein there are provided five concave wires per 10cm of width.

14. An apparatus as claimed in any one of claims 1 to 13 wherein said crop rubbing bars have a backward inclination with respect to said radial direction in the range of from 20' to 60° tangentially to the periphery of the concave.

15. An apparatus as claimed in any one of claims 1 to 14 wherein said crop rubbing bars have a tip portion for cooperation with said respective rotors which is kinked back in the range of from 40° to 80° tangentially to the periphery of the concave .

16. An apparatus as claimed in any one of claims 1 to 15 wherein said crop rubbing bars are spaced apart in the range of from 20mm to 30mm.

17. An apparatus as claimed in of claim 16 wherein said crop rubbing bars are spaced apart by 24mm.

18. An apparatus as claimed in any one of claims 1 to 17 wherein said second portion of said first concave and said first and second portions of said second concave are of a substantially identical construction.

19. A mobile harvesting machine comprising a whole crop harvesting and/or separating apparatus as claimed in claim 1 provided with a cutting table,- a crop gathering chamber; a crop elevator chamber; and grain conveying augers.

20. A mobile harvesting machine as claimed in claim 19 formed and arranged to be mounted to the three point linkage of a tractor.

21. A mobile harvesting machine as claimed in claim 19 or 20 provided with chassis means and wheels, said chassis means being formed and arranged for connection to a tractor linkage or the like for drawing the harvesting machine.

22. A whole crop harvesting and/or separating apparatus substantially as described hereinbefore and with reference to Fig. 1 and Fig. 3.

23. A whole crop harvester and/or separating apparatus having first and second concave portions substantially as described hereinbefore and with reference to Figs. 2a and 2b.