GB2207847A - Crop harvesting apparatus and methods - Google Patents

Abstract

Apparatus for harvesting crop comprises a mobile frame (12) for movement over the ground and a rotor (11) mounted for driven rotation in the overshot mode about an axis transverse to the intended movement of the apparatus. The rotor has a core (13) and a plurality of crop stripping elements (15) mounted on the core. The elements (15) are arranged in a single row, or preferably two or three rows on the rotor (11). The profile of the rotor core (13) following a row approaches the axis of the rotor so that a stem of crop caught by the stripping elements (15) and pulled taut by the rotation of the stripping elements does not touch the rotor core until the head of the stem is stripped from the stem. Where elements (15) are arranged in three rows, two rows of the elements may be adapted to detach required crop parts from normal crop, and the third row of elements may be adapted to detach required crop parts at a height lower than the average height of normal crop. <IMAGE>

Description

CROP HARVESTING APPARATUS AND METHODS The present invention relates to apparatus for, and methods of, harvesting crop. The invention is concerned with detaching from the stems or other plant parts of standing crop, seeds, seed-bearing parts, leaves, twigs, flowers, or other predetermined required portion of the crop, collecting the required portion, and leaving the remaining stripped parts of the crop standing in the field. The invention has particular but not exclusive application in the harvesting of grain crops, such as wheat, oats, barley, and rice.

The invention also has application in the stripping of leaves, young shoots, and sometimes blossom from crops.

Examples include lucerne (alfalfa) leaves for protein production, and the leaves and flowers of herbs and other crops used for the extraction of essential oils and other constituents.

There have been proposed previously a large number ot different forms of apparatus for detaching grain, or other required portions of a crop, from a standing crop, to leave the remaining stripped parts of the crop standing in the field. However none of these previous machines has found commercial acceptance, and all have various disadvantages. There are also known forms of apparatus having structural similarities to certain embodiments of the present invention, but adapted for use for different purposes.

It is an object of the present invention to provide improved apparatus for and methods of stripping required parts from a standing crop, usually the most valuable parts of the crop, namely the seed, leaves, and/or flowers.

According to the present invention in a first aspect there is provided apparatus for harvesting crop comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the frame about an axis transverse to the intended movement of the apparatus, the rotor having a core and a plurality of crop stripping elements mounted on the core and adapted for detaching from standing crop predetermined required parts of the crop, and drive means tor driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor, in which the crop stripping elements are arranged on the rotor in at least one row transverse to the intended direction of forward movement of the apparatus, and in which the profile of the rotor core following the said row approaches the axis of the rotor to an extent such that in operation a stem of crop caught by the stripping elements and pulled taut by the rotation of the stripping elements is not forced out of engagement with the stripping elements by contact of the stem with the core.

There are also provided a number of other aspects ot the present invention, and these relate to an apparatus for harvesting crop, referred to in this specitication as apparatus as hereinbefore defined, comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the trame about an axis transverse to the intended movement of the apparatus, the rotor having a plurality of crop stripping elements adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor.

According to the present invention in a second aspect there is provided apparatus as hereinbefore defined in which the crop stripping elements are arranged on a core of the rotor in two rows only, the rows being transverse to the intended direction of torward travel of the apparatus, the rotor core having a cross-section substantially in the shape of a non-rectangular parallelogram, each row of elements being attached to the core in the region of a respective acute-angle apex of the parallelogram.

According to the present invention in a third aspect there is provided apparatus as hereinbefore defined in which the crop stripping elements are arranged on a core of the rotor in three rows only, the rows being transverse to the intended direction of forward travel of the apparatus, the rotor having a cross-section substantially in the shape of an equilateral triangle, each row of elements being attached to the core in the region of a respective apex of the equilateral triangle.

According to the present invention in a further aspect there is provided apparatus as hereinbefore defined in which the crop stripping elements are arranged on a core of the rotor in at least one row transverse to the intended direction of forward movement of the apparatus, and in which the distance from the axis of rotation of the rotor to the periphery of the rotor core along a radius is, throughout the quadrant of the rotor following the row of elements, less than the distance from the axis of rotation to the periphery of the rotor core at the region of attachment of the row or elements to the core.

Preferably the said distance to the periphery of the core will be less than that at the row of elements, throughout a following sector which is greater than a quadrant.

Normally in preferred arrangements, both the said transverse axis of rotation of the rotor and the said at least one transverse row of elements will be arranged at right angles to the intended direction of forwara travel of the apparatus.

By the term standing crop is meant crop in the field before any harvesting operation has been carried out on it, for example before any cutting operation, and the term standing crop includes crop which may be laid, leaning, or twisted, as well as upright crop.

Normally it will be arranged that the depth of the rotor core from side to side along a diameter perpenaicular to a diameter through the region of attachment of the elements is less than the depth of the core along the said diameter through the region of attachment.

Although the elements may be arranged with only a single row of elements on the rotor core, it is preferred in one form that the elements are arranged in two rows only on the rotor core, positioned substantially opposite each other on a diameter of the rotor.

In another preferred form, it may be arranged that the elements are arranged in three rows only on the rotor, the rows being spaced apart substantially unitormly around the circumference of the rotor.

In some preferred embodiments the profile of the rotor core in the quadrant following the row of elements is a substantially flat plane inclined at an angle of less than 45 to a diameter through the region of attachment of the elements. Preferably the elements in the said row of elements lie substantially in a plane which is inclined to the said diameter through the attachment region, at the same angle as, or at a greater angle than, the said profile of the rotor core which follows the said row of elements. It may also be arranged that the profile of the rotor core in the quadrant preceding the row of elements is a substantially flat plane inclined at an angle of less than 45 to a diameter through the region of attachment ot the elements.

Considering now the shape of the crop stripping elements which may be used, it is preferred that at least some of the crop stripping elements provide at least one reverse facing edge facing away from the distal tip of the element for stripping crop parts which tace forwardly relative to the direction of movement of the apparatus.

Conveniently, the crop stripping elements may be tormed by the teeth of a transverse comb mounted on the rotor core and extending generally along a direction parallel to the axis of rotation, and preferably there is provided at the junction of adjacent side edges of adjacent teeth on the comb a relief aperture having edges adapted to strip the required parts from the crop stems. It is particularly preferred that the relief aperture includes at least one reverse facing edge which faces away from the distal tip of the element and is adapted to strip crop parts from regions of the standing crop which face forwardly relative to the intended direction of movement of the apparatus.

In preferred forms, each row of crop stripping elements is arranged substantially parallel to the axis ot rotation of the rotor, but in some arrangements the row may be curved along a part spiral path around the rotor, or may in other manner differ from a straight row parallel to the axis of rotation. In such cases, reverences to the shape of the rotor core, for example the shape in a quadrant following a row of elements, are intended to be references to the profile of a cross section of the core through any given part of the row ot elements being considered.Thus for example where it is said that the distance from the axis to the periphery ot the core is less throughout the following quadrant than at the row of elements, and where the row is not straight and parallel to the axis, then what is meant is that, taking a cross-section perpendicular to the axis, the distance from the axis to the periphery of the core is less than that at the row of elements throughout the following quadrant along that cross-section.

It is preferred that the elements provide a transverse surface for impelling the detached crop parts along a crop flow passage formed between the outer periphery of the envelope swept by the rotor and guide means such as a hood or cover co-operating with the elements.

By a transverse surface is meant a surface which lies substantially in a plane which extends principally across, but not necessarily at right angle to, the direction of movement of the element along the crop flow passage. The said transverse plane may be perpendicular to the said direction of movement of the element, but preferably the principal plane of each element is raked forwardly relative to the direction of movement of the element. The plane of the surface may conveniently be substantially flat, but in some arrangements may be curved, preferably slightly concave.

It is preferred that the drive means is arranged to drive the elements at a speed sufficiently high to impel the detached crop parts along the crop flow passage in such a manner that detached crop parts do not reside to any substantial extent on the moving crop stripping elements.

A number of criteria can be used to establish the required high speed, for example the speed of movement of the crop engaging elements relative to the frame will normally be set to be substantially greater than the forward speed of movement of the frame, and set at a speed such as to propel the stripped material in a fast moving stream along the crop flow passage defined between the guide means and the crop engaging elements.

Preferably the tip speed of the crop engaging elements is greater than 5 m/s, most preferably greater than 17 m/s. The forward speed of the frame may be in a range up to 10 km/hour, preferably in the range 4 to 12 km/hour, preferably greater 8km/hour.

In examples of preferred methods embodying the invention, a method of harvesting cereals may include moving the crop engaging elements relative to the frame at a speed such that the tip speed of the elements is in the range 10 to 25 m/s. In accordance with another preferred example, a method of harvesting lucerne (altaita) includes moving the crop engaging elements relative to the frame at a speed such that the tip speed of the elements is in the range 15 to 30 m/s.

In general, those aspects of the invention which have been described with reference to apparatus according to the invention, may also be provided with reference to methods of harvesting in accordance with the invention, and vice versa.

In particular there may be provided in accordance with the invention a method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements mounted on a rotor, detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps of catching a stem of standing crop by engaging the required part of the crop by the crop stripping elements (for example by catching a head of a stem of standing crop), and drawing the required part of the crop (for example the head of the stem) into the upper front third sector (preferably into the upper front quadrant) of the envelope swept by the rotor with the stem pulled taut by the rotation of the stripping elements, without the stem touching the core of the rotor, preferably without touching either the core or any further row of stripping elements on the rotor.

In accordance with a further aspect of the invention, there is provided a method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements mounted on a rotor, detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps ot catching a stem of standing crop by a row of crop stripping elements, drawing the stem upwardly by a combing action, and stripping off the required parts (e.g. grain particles or an entire head of grain) before the stem is contacted by any further row of stripping elements on the rotor.

In its main preferred aspect, it is an object of the invention to lift the crop, particularly long crop, into the upper front third sector of the envelope swept by the rotor, preferably the upper front quadrant of the rotor envelope, before stripping takes place. The reason for this is that grain losses are reduced the more the grain is stripped in the upper front quadrant, rather than the lower front quadrant. With previous known devices, long crop may be pushed downwardly and forwardly and be stripped by the elements in the lower tront quadrant, so that much grain is propelled forwardly and misses the lower front of the hood and is lost.

It is a particularly preferred feature of the invention that once a row of crop stripping elements has caught a stem and head, the head is lifted upwardly into the upper front quadrant of the rotor envelope, without the stem of the crop touching the rotor core until it is stripped. With known machines, the rotor core may contact a long stem and push the head out of engagement with the crop stripping elements before stripping takes place. The head is stripped eventually by succeeding rows of crop stripping elements, but only when it is in the disadvantageous forwardly laying position.It is a feature of the present invention in its main aspect that the rotor core profile falls away towards the rotor axis to allow the crop engaging element to carry the crop head into the advantageous upper tront quadrant, and the stem is able to remain taut between the roots and the head of the crop without touching the rotor core.

In accordance with another aspect, the invention lies in reducing the number of rows of crop stripping elements around the rotor, preferably to two rows diametrically opposed across the rotor. The reduction of the number of rows to two rows only has the advantage that a sideways lain stem can be caught in the stripping elements at the base of the stem and then can be drawn sideways as the stripping elements comb upwardly, until the previously sideways lain stem is held vertically upright and can be stripped at the end of the stem. This facility of combing the sideways lain crop to an upright position is not available with previously known multi-row rotors, because later following rows of crop stripping elements engage the sideways lain stem which is already engaged by a previous row, and snap off the stem.Thus it is an advantage to have the crop engaged by substantially one row of crop stripping elements at a time, since this allows them to be combed upright. Where stems are engaged by several rows at once, tangling and snapping takes place. An advantage of using fewer rows of crop stripping elements is that there is a lower power requirement, because of the ability of the rotor to straighten sideways lain crop.

In accordance with a further broad aspect of the invention there is provided apparatus as hereinbefore detined in which the crop stripping elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged in two rows only positioned substantially opposite each other on the rotor.

In accordance with a broad aspect of the invention there is provided apparatus as hereinafter defined in which the elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged on the rotor in three rows only.

Preterably the rotor has a core on which the elements aremounted, and said core has a cross-section substantially in the shape of an equilateral triangle, and most preferably the said three rows are arranged with each row attached to the core in the region of a respective apex ot the equilateral triangle.

In accordance with a yet further broad aspect of the invention, there is provided apparatus as hereinbefore defined in which the elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged on the rotor in four rows only, the rotor have a rotor core on which the said elements are mounted, the said core having a cross-section substantially in the shape of a square. Preferably the said rows of elements are arranged with each row attached to the core in the region of a corner of the said square.

According to the present invention in a second main aspect there is provided apparatus for harvesting crop comprising a mobile frame for movement over the grouna, moveable support means mounted for driven movement relative to the frame, a plurality of projecting crop engaging'elements mounted on the moveable support means and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the moveable support means to carry the elements upwardly at a front region of the apparatus, in which the crop engaging elements vary in shape and/or size and/or inclination in such a manner that some elements are adapted to detach required crop parts at a first height or range of heights (corresponding to normal crop), and other elements are adapted to detach required crop parts at a lower height or range of heights (corresponding to crop having the required crop parts at a height lower than the average height of normal crop).

According to the present invention in a further aspect there is provided apparatus as hereinbefore defined in which the elements are arranged in at least one transverse row in which each element is inclined to a radius through the tip of the element at a first acute angle, and at least one transverse row of elements in which each element is inclined to a radius through the tip of the element at an acute angle greater than the said first angle.

According to the present invention in a yet further aspect, there is provided apparatus as hereinbefore defined in which the elements are arranged in transverse rows with crop gathering spaces defined between adjacent elements in the rows, there being provided at least one row in which each element is inclined to a radius through the innermost edge of the crop gathering space defined by that element at a first acute angle, and at least one row in which each element is inclined to a radius through the innermost edge of the crop gathering space defined by that element at a second acute angle which is greater than the said first angle.

By a transverse row is meant a row of elements which extends across, but not necessarily at right angles to, the intended direction of forward travel of the apparatus over the ground.

Preferably the elements are arranged in three rows only on the said rotor, and two of said rows have elements inclined at the said first angle, and one ot said rows has elements inclined at the said greater angle. Preferably the rotor has a core on which the elements are mounted, and said core has a cross-section in the shape of an equilateral triangle, the said three rows being arranged with each row attached to the core in the region of a respective apex of the equilateral triangle.

In an alternative preferred arrangement the said elements are arranged in four rows only on the rotor, and three of said rows of elements have the elements inclined at said first angle, and one of said rows has said elements inclined at said second greater angle.

In this arrangement, preferably the rotor has a rotor core on which the said elements are mounted, the said core having a cross-section in the shape of a square, the said rows of elements being arranged with each row attached to the core in the region of a corner of the said square.

Preferably said first angle of said elements lies in the range 15 to 25', and preferably the said second angle lies in the range 25' to 45'.

Also preferably the said second, greater angle at which the elements are inclined is at least 5' greater than said first mentioned angle, most preferably approximately 10' greater than the first mentioned angle.

In some preferred arrangements the said elements which are inclined at the greater angle are longer than those elements inclined at the lesser angle, by an amount such that the tips of the elements lie on the same cylindrical envelope swept by the outer periphery of the rotor.

It is a generally preferred feature in all the arrangements set out above that the surface of the rotor core immediately preceding a row of elements is spaced from the axis of rotation of the rotor at a sufficient distance, and at such an angle, that detached crop parts falling on the surface are in operation impelled from the said preceding surface along a crop flow passage.

There may further be provided in accordance with the invention a method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps of detaching required crop parts from the upper part of a normal, upright crop by crop engaging elements presenting a required inclination to the crop at the time of stripping the crop, and detaching required crop parts from a minority of the crop which has its required crop parts at a lower level than the majority of the crop, by means of crop engaging elements presented to the crop substantially at the same required angle, but at a lower level than the elements presented to the upper part of the crop.

Preferably the method includes the step of presenting first crop engaging elements to the upper crop parts at the said required angle, and further crop engaging elements to the lower parts of the crop at the said required angle.

Preferably the said required angle at which the elements are presented to the crop is substantially horizontal, or upwardly inclined.

In one aspect the invention is concerned with a problem which arises in grain stripping of standing wheat and oats, where there sometimes occur grain losses of the order of 2 to 4 per cent. It is believed that these losses are due to a proportion of the crop being lodged in a crop which is otherwise an upright standing crop. It is believed that there is a percentage of the crop heads which are lying at a lower level than the main crop horizon, and that these heads are stripped in a known grain stripper in such a manner that stripped heads or grain are directed forwardly under the overhead hood and are lost.

One object of the invention is to produce a form of stripping rotor which will strip and collect grain trom the occasional lodged stem, whilst not interfering with the stripping of the bulk of normal standing crop.

A preferred solution is to have a three row rotor with a core having an equilateral triangular cross-section, two rows of stripping elements being of normal contiguration for stripping standing crop, and a third row of elements being more forwardly inclined so as to strip low ears in the crop.

In another aspect, the invention is concerned with the problem which may occur when, in a known grain stripping rotor, a substantial plurality of rows of stripping elements are provided around the rotor, for example eight. In these circumstances it is believed that a crop head can be pushed out of the row of elements by which it has been caught, by contact of the stem of the crop with the rotor core, or with a subsequently following row of crop stripping elements.

It is believed to be advantageous to arrange a lesser number of rows of crop stripping elements around the rotor, and to shape the rotor core in such a manner that the stems of crop caught by a row of elements are not contacted by the rotor core, or by following rows of elements, until the element has been lifted into the correct position for stripping, and the crop has been stripped by the elements.

It is believed that in some uses a three sided rotor core is the best compromise between a number of reactors. The main advantage is the same as for, for example, a two row rotor core, namely that the surface following the row of stripping elements falls away towards the core centre and therefore does not contact the stem of crop being stripped until after the head has been stripped. It is believed that a three sided rotor core is better in some conditions then a two row rotor, because the surface preceding the row of elements performs better in throwing the grain upwardly along the required trajectory.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a diagrammatic side view in section of apparatus for harvesting crop, embodying the present invention in a first aspect; Figure la shows a diagrammatic side view of the apparatus of Figure 1 with the rotor of the apparatus rotated to a subsequent position; Figure 2 is a cross-section through a rotor embodying the invention, in the first aspect, and shows in more detail the construction of the rotor; Figure 3 shows a perspective view of one form of crop stripping elements which may be used in accordance with the invention in the apparatus of Figure 1, la or 2; Figure 4 is a diagrammatic side view in section of a further apparatus for harvesting crop, embodying the present invention;; Figure 5 is a cross-section through a rotor embodying the invention and shows in more detail the construction of the rotor; Figure 6 shows a perspective view of one form of crop stripping elements which may be used in accordance with the invention in the apparatus of Figure 4; Figure 7 is a cross-section through a rotor similar to that shown in Figures 5 and 6, but with the elements raked forwardly to a lesser degree than in the previous figures; and Figures 8 and 8(a) are cross-sections through rotors similar to that shown in Figures 5 to 7, but with the core modified so as to be curved between rows.

Referring firstly to Figures 1 and 2, the apparatus comprises a mobile frame 12 on which is mounted a rotor 11 carrying outwardly projecting crop stripping elements 15 adapted for detaching from standing crop predetermined required parts of the crop.

A hood or cover 18 extends over the rotor 11 and defines with the rotor elements 15 a crop flow passage along which crop is conveyed by the rotor. The rotor 11 is rotated in the so called overshot mode, so that the crop stripping elements 15 move upwardly at the front of the rotor.

In operation, rotation of the rotor 11 moves the crop stripping elements so that the elements protrude into the crop, gather the crop, and then move upwardly through the crop. As the elements 15 reach the seed heads of the crop, the required parts are detached either by rubbing, striking or otherwise detaching individual grains of crop, or by breaking whole grain heads from the stems.

After detachment, the required crop parts are conveyed upwardly and rearwardly over the rotor 11, and pass to crop conveying means positioned within the apparatus, in the example shown, a conveyor belt 25 leading to a transverse auger 27 in a collecting trough 28 for moving the crop laterally for onward conveying through the apparatus.

In Figure 3 there is shown a transverse array of crop stripping elements 15 constituted by a comb 14 mounted on a rotor core 13. Each comb may be formed from a transverse rib of solid material, preferably synthetic plastics material or rubber, shaped to provide an array of teeth forming the stripping elements 15 mounted in a row transverse to the direction or movement of the harvesting apparatus through the crop. Each tooth 15 has side edges 16 and 17 which diverge from each other in a direction away from the distal tip of the tooth 15. There is provided at the junction of each adjacent pair of teeth 15, an enlarged relief aperture 21, which in the example shown in Figure 3, is part circular. Each aperture 21 is formed by relieved portions of the adjacent teeth at the base regions thereof.In the example shown, each comb is formed from. a sheet-like rib of solid material having cut therein a series of keyhole shaped apertures, producing the said teeth 15.

The present invention has a number of aspects. In accordance with one main aspect, in the embodiments shown, there are provided only two rows of crop stripping elements 15, positioned diametrically opposite each other on a flattened core 13, shown particularly in Figure 2. In the preferred form shown, the rotor core 13 is generally a flattened diamond shape, and is formed of sheet steel pressed into the required shape in a number of sections, and bolted or welded together. The intended direction of rotation of the rotor is shown by the arrow A in Figure 2.

Considering the row of crop stripping elements 15 on the right of Figure 2, the comb 14 of elements 15 is bolted between a preceding core plate 30 which leads the element 15, and a trailing core plate 31 which tollows after the elements 15, relative to the direction of rotation. The comb 14 is bolted along a line shown diagrammatically at 32, between the preceding and trailing core plates 30 and 31.

In the preferred embodiment shown, the preceding core plate 30, the trailing core plate 31, and the comb 14 of elements, each lies substantially in a respective flat plane, and it has been found that the angular relationship between these planes relative to each other and relative to a radius of the rotor through the region of attachment of the elements 15, is of signiticance in the etticient stripping and conveying of crop.

In Figure 2, a radius C is shown passing through the axis of rotation of the rotor, and through the junction B of the core plate 30 and the leading face of the comb 14. The relationship between the various planes of the core and the element can be appreciated by considering their angles to the radius C. The angle between the leading face of the stripping elements 15 and the radius C is indicated as < , and is preferably in the range 20' to 30', preferably approximately 25'.

The angle between the preceding core plate 30 and the radius C indicated at P , and preferably is less than 45', preferably between 25' and 30'. The angle between the trailing core plate 31 and the radius B is shown atg and preferably is less than 45 preferably in the range 159 to 25'.

Referring now to Figures 1 and la, the operation of the apparatus will be described. A stem of crop, for example 35, is initially caught by the comb 14 of the stripping elements 15, when the comb 14 is pointing downwardly and forwardly, at say the five o'clock position (not shown). The rotation of the rotor 11 brings the elements 15 to approximately the 3 o'clock position shown in Figure 1, and during this movement the elements 15 comb upwardly through the stems catching the head 36 of the stem 35 and drawing it into the upper third sector of the rotor 11, that is to say the sector between the four o'clock position and the twelve o'clock position for an anti-clockwise rotation.As shown in Figure la, further rotation of the rotor 11 draws the head 36 into approximately the 2 o'clock position shown, at which position the stem 35 is pulled substantially taut, and the grain or the entire head 36 is detached from the stem 35 before the next following row of elements 15 begins to engage the stem 35.

It is an important preferred feature of the present invention, at least in preferred forms, that the rotor core 13 is flattened as shown along a diameter perpendicular to the diameter on which the elements 15 are mounted. The purpose of this is that the stem 35 does not contact the core 13 (Figure 1) while the head 36 is being drawn into the front upper third sector of the rotor. Such contact would be likely to push the head 36 out of engagement with the elements 15. Thus, in the example shown in Figure 2, the profile 31 of the rotor core 13 following the row 14 of elements 15 approaches the axis of the rotor 11 to an extent such that in operation a stem of crop caught by the stripping elements and pulled taut by the rotation of the stripping elements is not forced out of engagement with the stripping elements by contact of the stem with the core.

Next, it is a preferred feature that, as shown in Figure la, the next following row ot elements 15 does not contact the stem 35, until after the head 36 has been detached, or at about substantially the same time.

The advantage of this is that it allows the comb 14 which has engaged the stem 35, to comb the stem and to bring the stem into an upright position if the stem has previously been lain laterally relative to the direction of forward movement of the apparatus.

In a modification of the rotor shown in Figures 1, la and 2, there may be provided only a single row of crop stripping elements 15, and the rotor core may be reshaped on the side diametrically opposite to the row of stripping elements, so as to provide a suitably curved rotor profile. The rotor core is then provided with a counter balance weight on the side remote from the row of stripping elements, so as to ensure balanced rotation.

Referring firstly to Figures 4 and 5, the apparatus comprises a mobile frame 112 on which is mounted a rotor 111 carrying outwardly projecting crop stripping elements 115 adapted for detaching from standing crop predetermined required parts of the crop.

A hood or cover 118 extends over the rotor 111 and defines with the rotor elements 115 a crop flow passage along which crop is conveyed by the rotor. The rotor 11 is rotated in the so called overshot mode, so that the crop stripping elements 115 move upwardly at the front of the rotor.

In operation, rotation of the rotor 111 moves the crop stripping elements so that the elements protrude into the crop, gather the crop, and then move upwardly through the crop. As the elements 115 reach the seed heads of the crop, the required parts are detached either by rubbing, striking or otherwise detaching individual grains of crop, or by breaking whole grain heads from the stems.

After detachment, the required crop parts are conveyed upwardly and rearwardly over the rotor 111, and pass to crop conveying means positioned within the apparatus, in the example shown, a transverse auger 127 in a collecting trough 128 for moving the crop laterally for onward conveying through the apparatus by a conveyor 125.

In Figures 5 and 6 there are shown three transverse rows 114A, 114B and 114C of crop stripping elements 115 constituted by combs mounted on a rotor core 113. Each comb may be formed from a transverse rib of solid material, preferably synthetic plastics material or rubber, shaped to provide an array of teeth forming the stripping elements 115 mounted in a row transverse to the direction of movement of the harvesting apparatus through the crop (in the example shown, at right angles to the direction). Each tooth 115 has side edges 116 and 117 which diverge from each other in a direction away from the distal tip of the tooth 115. There is provided at the junction of each adjacent pair of teeth 115, an enlarged relief aperture 121, which in the example shown in Figure 6, is part circular. Each aperture 121 is formed by relieved portions of the adjacent teeth at the base regions thereof.In the example shown, each comb is formed from a sheet-like rib of solid material having cut therein a series of keyhole shaped apertures, producing the said teeth 115.

The present invention has a number of aspects. In accordance with one main aspect, in the embodiments shown, there are provided only three rows of crop stripping elements 115, positioned at the respective apexes of the core 113 which is of equilateral triangular cross-section, shown particularly in Figure 5. In the preferred form shown, the rotor core 13 is formed of sheet steel pressed into the required shape in a number of sections, and bolted or welded together.

The intended direction of rotation of the rotor is shown by the arrow A in Figure 5.

Considering the row 114A.of crop stripping elements 115 on the right of Figure 5, the comb of elements 115 is secured between a preceding core plate 130 which leads the element 115, and a trailing core plate 131 which follows after the elements 115, relative to the direction of rotation.

In the preferred embodiment shown, the preceding core plate 130, the trailing core plate 131, and the comb ot elements 115, each lies substantially in a respective flat plane, and it has been found that the angular relationship between these planes relative to each other and relative to a radius of the rotor through the region of attachment of the elements 115, is of significance in the efficient stripping and conveying of crop.

In Figure 5, a radius R is shown passing through the axis of rotation of the rotor, and through the base of the "keyhole1 aperture, i.e. the innermost part of the reliet aperture 120. The relationship between the various planes of the core and the element can be appreciated by considering their angles to the radius R. The angle between the leading face of the stripping elements 115 in row 114A and the radius R is indicated as X, and is preferably in the range 15' to 25, preferably approximately 20'.

In Figure 5, the row 114B is identical to the row 114A which has been described, has an angle of inclination Y which is the same as X, and operates in the same manner. However the row 114C has the elements 115 raked more forwardly compared with the rows 114A and 114B. In the case of the row 114C a radius R through the axis of rotation of the rotor, and through the base of a keyhole aperture in the row, makes an angle Z with the plane of the elements 115. The angle Z is greater than the angle X, and is preferably in the range 25" e to 45-, most preferably 30'. Thus the angle at which the elements of the row 14C are inclined relative to a radius through the element is greater than the similar angle for the elements 115A of row 114A, by an amount preferably of 10'.

The purpose of the greater angle of rake of the elements of the row 114C is as follows. It is believed that stripping takes place best when the stripping elements are presented with the principal plane of the elements substantially horizontal, or slightly upwardly inclined, at the moment of presentation of the element to the crop head. For normal upright crop, this takes place, as shown in Figure 4, at approximately the front central position of the envelope swept by the rotor, also referred to as the 3 o'clock position. However for a lodged head, for example as shown at 136A, the normal rows of stripping elements 114A and 114B will be presented to the lodged head 136A at a downwardly inclined attitude, because of the lower height of the lodged head 136A. This will result in the stripped head, or grain therefrom, being propelled forwardly under the hood, with a likelihood of being lost.

However, the more forwardly inclined elements 115 of row 114C, will arrive at the correct horizontal or slightly upwardly inclined attitude, at a lower level than the rows 114A and 114B. Therefore the raked row 114C will be presented to the lodged head 136A at a lower level than the combs 114A and 114B, but with the correct attitude of a horizontal or slightly upwardly inclined attitude. The result is that the more forwardly inclined row 114C tends to strip crop having the required crop parts at a lower level than the average height of the normal upright crop.

Reterring now to Figure 4, the operation of the apparatus will be described. A stem of crop, for example 135, is initially caught by the comb 114A of the stripping elements 115, when the comb is pointing downwardly and forwardly, at say the 5 o'clock position (not shown). The rotation of the rotor 111 brings the elements 115 to approximately the 3 o'clock position shown in Figure 4, and during this movement the elements 115 comb upwardly through the stems catching the head 136 of the stem 135 and detaching the grain or the entire head 136 from the stem 135 before the next following row of elements 115 begins to engage the stem 135.

It is an important preferred feature of the present invention, in preferred forms, that the rotor core 113 is shaped as shown. The purpose of this is that the stem 135 does not contact the core 113 (Figure 4) while the head 136 is being drawn upwardly. Such contact would be likely to push the head 136 out of engagement with the elements 115. Next, it is a preferred feature that, as shown in Figure 4a, the next following row of elements 115 does not contact the stem 135, until atter the head 136 has been detached, or at about substantially the same time.

In Figure 7 there is shown a rotor similar to that of Figures 5 and 6, but with the combs of elements 115 less forwardly inclined. In Figure 7 the preferred angles are shown, that is to say X = 20', Y = 20' and Z = 30'.

Figure 8 shows in cross-section a modification of the rotor shown in Figure 5. The modification is that the rotor core 113 has a curved profile between the rows of crop stripping elements 115. The curves of the three sectors of the rotor core are indicated by the reference numeral 113A, 113B and 113C, and the curves are formed by part circles drawn about centres indicated by crosses at A, B, C respectively.

The construction is generally the same as has been described previously. A series of supporting members are spaced along the axis of rotation of the rotor, each of them having the lobed shape shown if Figure 8, and the actual profile of the core being formed by sheet metal cladding mounted on the shaped support members. Each row of crop stripping elements 115 is secured to a step or shoulder 133 by a captive nut 134 which is welded to the inside of the shoulder 133. The comb of elements 115 is secured by a bolt (not shown) passing into the captive nut 134.

In corresponding manner to the embodiment of Figure 5, the three rows of elements are labeled 114A, 114B, and 114C. The rows 114A and 114B are identical, but the row 114C is inclined forwardly at a greater angle than the other two rows, and is of greater length, so that its tip lies in the same cylindrical envelope swept out by the outer periphery of the rotor 111.

In Figure 8a, there is shown a further modification, in which all three rows of crop stripping elements 115 are identical, and are set at the same angle of rake.

In Figures 8 and 8a, the intended direction of rotation of the rotor is indicated by the arrows A.

It will be appreciated that many of the concepts of the present invention can be applied equally well to a moveable support means on which the elements are mounted, which is not a rotor, for example which is an endless conveyor. Where appropriate, the various aspects of the present invention apply equally to a moveable support means comprising a rotor, or comprising a conveyor.

Claims (31)

1. Apparatus for harvesting crop comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the frame about an axis transverse to the intended movement of the apparatus, the rotor having a core and a plurality of crop stripping elements mounted on the core and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor, in which the crop stripping elements are arranged on the rotor in at least one row transverse to the intended direction of forward movement of the apparatus, and in which the profile of the rotor core following the said row approaches the axis of the rotor to an extent such that in operation a stem of crop caught by the stripping elements and pullea taut by the rotation ot the stripping elements is not forced out of engagement with the stripping elements by contact of the stem with the core.

2. Apparatus for harvesting crop comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the frame about an axis transverse to the intended movement of the apparatus, the rotor having a core and a plurality of -crop stripping elements mounted on the core and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor, in which the crop stripping elements are arranged on the rotor in two rows only, the rows being transverse to the intended direction of torward travel of the apparatus, the rotor core having a cross-section substantially in the shape of a non-rectangular parallelogram, each row of elements being attached to the core in the region of a respective acute-angle apex of the parallelogram.

3. Apparatus for harvesting crop comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the frame about an axis transverse to the intended movement of the apparatus, the rotor having a core and a plurality of crop stripping elements mounted on the core and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor, in which the crop stripping elements are arranged on the rotor in three rows only, the rows being transverse to the intended direction of forward travel of the apparatus, the rotor having a cross-section substantially in the shape of an equilateral triangle, each row of elements being attached to the core in the region of a respective apex of the equilateral triangle.

4. Apparatus for harvesting crop comprising a mobile frame for movement over the ground, a rotor mounted for driven rotation relative to the frameabout an axis transverse to the intended movement of the apparatus, the rotor having a core and a plurality of crop stripping elements mounted on the core and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the rotor in a sense such as to carry the elements upwardly at the front of the rotor, in which the crop stripping elements are arranged on the rotor in at least one row transverse to the intended direction of forward movement of the apparatus, and in which the distance from the axis of rotation of the rotor to the periphery of the rotor core along a radius is, throughout the quadrant of the rotor following the row of elements, less than the distance from the axis of rotation to the periphery of the rotor core at the region of attachment of the row of elements to the core.

5. Apparatus according to claim 4 in which the depth of the rotor core from side to side along a diameter perpendicular to a diameter through the region of attachment of the elements of the or a row, is less than the depth of the core along the said diameter through the region of attachment.

6. Apparatus according to claim 4 or 5 in which the elements are arranged in two rows only on the rotor core, positioned substantially opposite each other on a diameter of the rotor.

7. Apparatus according to claim 4 or 5 in which the elements are arranged in three rows only on the rotor, the rows being spaced apart substantially uniformly around the circumference of the rotor.

8. Apparatus according to claim 4, 5, 6, or 7 in which the profile ot the rotor core in the quadrant tollowing the row of elements is a substantially flat plane inclined at an angle of less than 45e to a diameter through the region of attachment of the elements.

9. Apparatus according to claim 8 in which the elements in the said row of elements lies substantially in a plane which is inclined to the said diameter through the attachment region, at the same angle as, or at a greater angle than, the said angle of less than 45" of the protile of the rotor core.

10. Apparatus according to any of claims 4 to 9 in which the profile of the rotor core in the quadrant preceding the row of elements is a substantially tlat plane inclined at an angle of less than 45' to a diameter through the region of attachment of the elements.

11. Apparatus according to of claims 2 to 10 in which the protile of the rotor core following the said row approaches the axis of the rotor to an extent such that in operation a stem of crop caught by the stripping elements and pulled taut by the rotation of the stripping elements is not forced out of engagement with the stripping elements by contact of the stem with the core.

12. Apparatus according to any preceding claim in which at least some of the crop stripping elements provide at least one reverse facing edge facing away from the distal tip of the element for stripping crop parts which face forwardly relative to the direction of movement of the apparatus.

13. A method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements mounted on a rotor, detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps of catching a stem of standing crop by engaging the required part of the crop by the crop stripping elements, and drawing the required part of the crop into the upper front third sector of the envelope swept by the rotor with the stem pulled taut by the rotation of the stripping elements, without the stem touching the core of the rotor.

14. A method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements mounted on a rotor, detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps of catching a stem of standing crop by a row of crop stripping elements, drawing the stem upwardly by a combing action, and stripping oft the required crop parts before the stem is contacted by any further row of stripping elements on the rotor the core.

15. Apparatus for harvesting crop as hereinbefore defined in which the crop stripping elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged in two rows only positioned substantially opposite each other on the rotor.

16. Apparatus for harvesting crop as hereinbefore defined in which the elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged on the rotor in three rows only.

17. Apparatus for harvesting crop as hereinbefore defined in which the elements are arranged on the rotor in rows transverse to the intended direction of forward movement of the apparatus, and are arranged on the rotor in four rows only, the rotor having a rotor core on which the said elements are mounted, the said core having a cross-section substantially in the shape of a square.

18. Apparatus according to claim 17 in which the said rows of elements are arranged with each row attached to the core in the region of a corner of the said square.

19. Apparatus for harvesting crop comprising a mobile frame for movement over the ground, moveable support means mounted for driven movement relative to the frame, a plurality of projecting crop engaging elements mounted on the moveable support means and adapted for detaching from standing crop predetermined required parts of the crop, and drive means for driving the moveable support means to carry the elements upwardly at a front region of the apparatus, in which the crop engaging elements vary in shape and/or size and/or inclination in such a manner that some elements are adapted to detach required crop parts at a first height or range of heights, and other elements are adapted to detach required crop parts at a lower height or range of heights.

20. Apparatus for harvesting crop as hereinbefore defined in which the elements are arranged in at least one transverse row in which each element is inclined to a radius through the tip of the element at a first acute angle, and at least one transverse row in which each element is inclined to a radius through the tip of the element at an acute angle greater than the said first angle.

21. Apparatus for harvesting crop as hereinbefore defined in which the elements are arranged in transverse rows with crop gathering spaces defined between adjacent elements in the rows, there being provided at least one row in which each element in that row is inclined to a radius through the innermost edge of the crop gathering space defined by that element at a first acute angler and at least one row in which each element is inclined to a radius through the innermost edge of the crop gathering space defined by that element at a second acute angle which is greater than the said first angle.

22. Apparatus according to claim 20 or 21 in which the elements are arranged in three rows only on the said rotor, and two of said rows have elements inclined at the said first angle, and one of said rows has elements inclined at the said greater angle.

23. Apparatus according to any of claims 20 to 22 in which said first angle of said elements lies in the range 15 to 25 , and the said second angle lies in the range 25 to 45".

24. Apparatus according to any of claims 20 to 23 in which the said second, greater angle at which the elements are inclined is at least 5 greater than said tirst mentioned angle.

25. Apparatus according to any of claims 20 to 24 in which the said elements which are inclined at the greater angle are longer than those elements inclined at the lesser angle, by an amount such that the tips of the elements lie on the same cylindrical envelope swept by the outer periphery of the rotor.

26. Apparatus according to any preceding claim in which the rotor has a core such that the surface of the rotor core immediately preceding a row of elements is spaced from the axis of rotation of the rotor at a sufficient distance, and at such an angle, that detached crop parts falling on the surface are in operation impelled from the said preceding surface along a crop flow passage.

27. A method of harvesting crop comprising moving through a standing crop a harvesting apparatus, moving upwardly at a front region of the apparatus a plurality of crop stripping elements, detaching from standing crop predetermined required parts of the crop, and collecting the detached crop parts, the method including the steps of detaching required crop parts trom the upper part of a normal, upright crop by crop engaging elements presenting a required inclination to the crop at the time of stripping the crop, and detaching required crop parts from a minority of the crop which has its required crop parts at a lower level than the majority of the crop, by means of crop engaging elements presented to the crop substantially at the same required angle, but at a lower level than the elements presented to the upper part of the crop.

28. A method according to claim 27 including the step of presenting first crop engaging elements to the upper crop parts at the said required angle, and further crop engaging elements to the lower parts of the crop at the said required angle.

29. A method according to claim 27 or 28 in which the said required angle at which the elements are provided to the crop is substantially horizontal or upwardly inclined.

30. Apparatus for harvesting crop substantially as hereinbefore described with reference to any one or any combination of the accompanying drawings.

31. A method of harvesting crop substantially as hereinbefore described with reference to any one or any combination of the accompanying drawings.