Agricultural harvesting machine for root crops

Abstract: There is disclosed a root crop harvesting machine, especially a potato harvesting machine (10) which can dig-­ up two rows (11) of crop and then discharge the crop laterally of the machine to any required extent via an elevator (14) which is adjusted to a lateral discharge mode, as shown in Figure 1, to permit the dug-up crop to be deposited in rows (18) for drying purposes. Once drying has been completed, the same machine (10) can then be used to pick-up the dried crop and then, following adjustment of the elevator (14) to an elevational position, the dried crop can be discharged into a collecting vehicle (21). The harvesting machine of the invention therefore has two discharge functions, and can replace two existing pieces of equipment. The invention also enables novel methods of crop harvesting to be carried out.

Description: This invention relates to an agricultural harvesting machine for root crops, such as potatoes. As is well known, potatoes are grown in the field in earthed-up rows, with furrows being left along each side of the rows, and once the potatoes are ready for harvesting, a potato harvester is drawn behind a tractor and usually is able to dig under and lift-up the potatoes and any attached soil of two rows at one time during each pass down the field. During each pass, the wheels of the tractor and of the trailed harvester run in the furrows between adjacent rows of potatoes. Most existing harvesters either have a temporary box store which is filled progressively with potatoes and then emptied at required intervals, or else discharges the potatoes as they are harvested to a separate collector vehicle which moves with and alongside the harvester. One known type of potato harvester is disclosed in US-A-3750858 and which comprises a wheel-supported frame, a digging mechanism at the forward end of the machine, means provided on the machine to separate crop from any soil and small stones dug-up at the same time as the crop, means for directing the separated crop to a discharge station, and a discharge elevator mounted on one side of the machine adjacent to the discharge station and comprising a main portion which is pivotally mounted at one end to the frame of the machine and a tail portion which is pivotally connected to the main portion. The elevator serves to transfer crop from the machine to a collecting vehicle which will be located alongside the machine, and a piston and cylinder assembly is used to raise and lower the main portion and the tail portion of the elevator as a single unit in order to vary the height of the discharge end of the tail portion of the elevator relative to the base of the collecting vehicle into which the crop is deposited. This enables the discharge end of the tail portion to be located closely adjacent to this base during initial loading of the collecting vehicle, and as the level of crop rises, the height of the discharge end can be raised accordingly, thereby to minimise the free fall under gravity of crop from the discharge end and minimise damage to the crop. However, in this known machine, it only has a single mode of operation to transfer crop from the machine i.e. to the collecting vehicle. Furthermore, the means by which the tail portion is connected to the main portion of the elevator comprises a complicated arrangement of chains, and which allow the tail portion to take-up a position in which it forms a prolongation of the main portion so that crop can be transferred from the machine only for a narrow range of pivotable adjustment of the main portion and tail portion of the elevator about the pivotable mounting on the frame of the machine. The main portion and tail portion of the elevator can be pivoted downwardly about this pivotable mounting, as a preliminary step in adjustment of the elevator portions to take-up a transport position, but the elevator would be quite incapable of effecting satisfactory lateral discharge of crop from the machine during this downward adjustment movement. In particular, as the two portions of the elevator pivot downwardly about the pivotable mounting, the arrangement of chains allow the tail portion to pivot under gravity relative to the main portion until such time as the discharge end of the tail portion comes into contact with the ground, and then the chains are removed and the tail portion is folded upwardly and inwardly to take-up a transport position, as shown in Figure 1 of the reference. Therefore, the reference teaches a sole mode of transfer of crop from the machine to the collecting vehicle, with limited vertical adjustment of the height of the discharge end of the tail portion of the elevator during crop transfer, and no facility for independent adjustment of the tail portion of the elevator relative to the main portion. This reference does not teach the possibility of laterally discharging crop from the machine via the main portion and tail portion of the elevator and with the discharge end of the tail portion located close to the ground surface so as to minimise the vertical path of travel of the crop from the discharge end to the ground. The known machine is satisfactory for the traditional methods of harvesting potatoes which are intended for consumption but there is a growing demand by some farmers and especially those who grow potatoes to the higher standard required for seed potatoes, to enable potatoes which have just been lifted from the ground to be deposited onto the field so as to be thoroughly dried (usually for a few hours) before being picked-up again. This is somewhat similar to the partial drying of newly cut grass to form hay. With a view to meeting this need, a digger windrower has been developed in the United States by Lockwood Corporation, and which has the function of lifting-up two rows of potatoes in the ground, in the manner of a conventional potato digger or harvester, and then after separation of soil and stones also lifted-up with the potatoes during rearward passage through the machine, the potatoes are discharged to one side of the machine to form a single deposited row. Therefore, during each pass along the field, two rows of potatoes can be dug-up, and then discharged laterally to form a single row which can be allowed to dry for a required length of time. A conventional potato harvester can then be used after the required drying has been completed, in order to pick-up the potatoes in the drying rows. This known digger windrower is therefore able to meet the requirements of some farmers who wish to return harvested potatoes onto the ground for drying purposes prior to further collection of the dried potatoes. However, this involves the use of a separate harvester to pick-up the rows of deposited and dried potatoes, and therefore two separate pieces of capital equipment are required to complete the overall potato harvesting operation, which of course is an additional cost as compared with normal potato harvesting (without drying in rows in the field) when only a single harvester is required. There is therefore a need to provide a single piece of agricultural equipment which is able to dig-up root crops in the ground, such as potatoes, or to pick-up rows of dug crop previously deposited for drying purposes, but which has a dual discharge function of being able in one mode of operation to discharge the dug crop laterally of the equipment to form a row of crop lying on the ground for any required air drying, and in a further mode of operation to discharge the crop to a collecting vehicle. According to one aspect of the invention there is provided a harvesting machine for root crops growing in substantially parallel rows in the ground and which comprises: a wheel-supported frame which is movable over the ground in a direction parallel to said rows with the wheels running in the spaces defined between the rows; a digging mechanism at the forward end of the machine and extending laterally by a sufficient extent to enable two adjacent rows of crop to be dug-up at the same time; means provided on the machine for separating the crop from any soil and small stones dug-up at the same time as the crop; means for directing the separated crop to a discharge station; and, a discharge elevator pivotally mounted on one side of the machine adjacent to the discharge station via a pivotable mounting and comprising a main portion mounted at one end on the pivotable mounting and a tail portion which is pivotally connected to the main portion, said elevator being adjustable about said pivotable mounting in order to vary the height of the discharge end of the tail portion when the elevator is being used in a crop transfer mode of operation to transfer crop from the machine to a collecting vehicle located alongside the machine; characterised in that the main portion and the tail portion are downwardly adjustable from the crop transfer position about the pivotable mounting so as to take-up a lateral deposition mode for depositing crop in a parallel row alongside the path of travel of the Machine on the ground, and in that the tail portion is adjustable relative to the main portion so that the discharge end of the tail portion can be located close to the ground and at any required lateral spacing from the machine. Thus, the invention provides a single piece of agricultural equipment which can be operated in the manner of a conventional harvester in order to dig-up crop growing in rows in the ground (especially potatoes), or to raise crop previously dug-up and then deposited in rows on the ground, and in which the harvester machine can be readily adjusted to operate in either one of two required discharge modes, namely the lateral deposition mode in which the discharge end of the tail portion of the elevator is located close to the ground when air drying of the crop in rows on the ground is required, and the lateral elevation mode when the crop is required to be collected in an adjacent collecting vehicle. In the lateral deposition mode of operation, the main portion of the elevator may be adjusted so as to extend substantially horizontal, or at a small upward inclination to the horizontal, and the tail portion is adjusted to extend downwardly of the end of the main portion so that its lower end can be located close to the ground surface and thereby reduce the distance through which the crop must fall onto the ground and minimise the risk of damage to the crop. The adjustment of the main and tail portions of the elevator conveniently also will be such that the crop can be deposited in one of the existing furrows located adjacent to the machine. The deposited crop is therefore held in the furrows while it undergoes any required air drying, prior to a further passage of the machine along the furrows in order to pick-up the dried crop. It will be appreciated that the machine can pick-up two rows of a growing crop, but will deposit these two rows into a single drying row. However, in one preferred mode of operation of the machine, the machine can be caused to follow a predetermined pattern of movement backwards and forwards over the rows of growing crop, such that during one forward passage two rows of a growing crop can be deposited into a single drying row, and during one reverse passage two further growing rows of crops can be deposited into the same drying row. The subsequent harvesting of the dried rows of crop will then involve only one quarter of the number of paths of travel required, as compared with that required for the initial digging-up of the growing crop. To permit further variation in the pattern of operation of the machine, the tail portion may be adjustable to occupy more than one position relative to the main portion, when in the lateral deposition mode of operation, so as to permit variation in the extent of lateral discharge of the crop from the machine. Thus, if deposit of the crop is required into furrows located nearer to the machine, the tail portion may be inwardly pivoted relative to the main portion so as to direct the crop to be deposited in any particular furrow. The use of a harvesting machine according to the invention therefore provides a capital cost saving by being able to perform the functions of two separate pieces of equipment, namely a digger windrower and a separate harvester. In addition, this can give economies in use of manpower, and also reduces the extent of soil compaction necessarily involved in moving pieces of agricultural equipment over the ground. Also, by careful control over the harvesting operation, it is possible to ensure that the headlands can be cleared of growing crop, and also the ground to one side of the machine at which a collecting vehicle will be positioned. According to a further aspect of the invention there is provided a method of harvesting root crops growing in substantially parallel rows in the ground, with longitudinal spaces defined between adjacent rows over which can travel the wheels of a propelling vehicle and a trailed harvesting machine coupled therewith, the machine having an elevator mounted thereon for discharging the harvested crop via a discharge end of the elevator, the method comprising : digging-up two adjacent rows of crop at a time with the harvesting machine during each passage of the machine; separating-out the crop in the machine from any soil and stones dug-up with the crop, and directing the crop to a discharge station in the machine; laterally discharging the crop from the machine via the elevator, when the latter is adjusted to a lateral discharge mode in which the discharge end is located close to the ground, to deposit the crop in a row extending substantially parallel to the dug-up rows, and while the machine is digging-up the crop in said rows during each passage of the machine; allowing the crop deposited in the row to dry to any required extent; picking-up the deposited crop after required drying using the same harvesting machine; and, elevating the crop via the elevator when the latter is adjusted to an elevation mode, so that the crop can fall under gravity into a collecting vehicle located alongside the harvesting machine. An embodiment of harvesting machine according to the invention, and a harvesting method utilising the machine will now be described in detail, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a rear view of an agricultural harvesting machine according to the invention for root crops, and illustrating the machine discharging the harvested crop via a lateral discharge elevator when adjusted to one mode of discharge operation; Figure 2 is a view, similar to Figure 1, showing the elevator adjusted to another discharge position in which the harvested crop can be elevated so as to fall under gravity into a collecting vehicle; Figure 3 is a rear view showing the elevator adjusted to an inward stowed or transport position; Figure 4 is a schematic plan view illustrating one method in accordance with the invention for harvesting a root crop growing in parallel rows in a field; Figure 5 is a schematic view, similar to Figure 4, showing a further method in accordance with the invention; and, Figure 6 is a schematic view showing the manner by which dug-up crop which has been deposited in rows in the field in the manner shown in Figure 1 can be picked-up and then elevated to be collected in a collecting vehicle alongside the harvesting machine. Referring first to Figures 1 and 2 of the drawings, an agricultural harvesting machine according to the invention is designated generally by reference 10, and is intended to be towed behind a propelling vehicle 40 (see Figures 4 to 6) and to have its operating components driven via the power take-off shaft of the propelling vehicle in well known manner, and as shown schematically in Figures 4 to 6. The machine 10 is intended to harvest root crops, and especially potatoes, growing in substantially parallel rows in the ground, with longitudinal spaces being defined between the adjacent rows over which can travel the wheels of the propelling vehicle and also those of the harvesting machine 10, without damaging the crop which is being harvested. In the case of potatoes, the crop grows in earthed-up rows 11, and the wheels then can run in the furrows 12 which are formed between each pair of adjacent rows of crop. Thus, as can be seen in Figure 1, the wheels 13 of the machine 10 can each run in a respective furrow defined between adjacent pairs of rows of crops 11. The forward and rear wheels of the propelling vehicle 40 also can travel in these furrows, as can be seen in Figures 4 to 6. The machine 10 therefore is provided with a wheel-supported frame which is movable over the ground in a direction parallel to the rows 11, and with the wheels running along the ground in the spaces defined between the rows. A digging mechanism 41 (shown schematically in Figure 4) is provided at the forward end of the machine, and extends laterally by a sufficient extent to enable two adjacent rows of crop to be dug-up at the same time during each passage of the machine from one end of the field to the other. The digging mechanism may take the form of any suitable design of digging mechanism as used in potato harvesting machines. The machine 10 will also be provided with suitable means (not shown) for separating the crop dug-up by mechanism 41 from any soil and small stones dug up at the same time, and means is also provided for directing the separated crop to a discharge station 43 (see Figure 4) at the rear of the machine. This separating and directing means may take the form of any suitable design as used in potato harvesting machines, and part of this is shown in the rear elevation of Figure 1 in the form of a conventional arrangement of endless travelling grid bars designated generally by reference 42. Adjacent to the discharge station, a discharge elevator 14 is pivotally mounted on one side of the machine frame, and can occupy a number of different positions of adjustment relative to the machine, as will become apparent from the subsequent description with reference to the drawings. The discharge elevator 14 comprises a main portion 15 which is pivotally mounted at one end 16 via a horizontal pivot 16a to the frame of the machine, and a tail portion 17 is pivotally connected to the main portion 15. The main portion 15 and the tail portion 17 are pivotally adjustable between a lateral deposition mode, as shown in Figure 1, which is a lateral discharge position for depositing crop in a parallel row alongside the path of travel of the machine and with only a small distance of travel under gravity of the crop from the discharge end of the tail portion 17 to the ground. As can be seen in Figure 1, potatoes 18 are being deposited in a row 19 which extends parallel to the rows of growing potatoes 11, and depositing the potatoes 18 in this row enables them to be dried-up for any required length of time, prior to being subsequently lifted again during a further passage of the harvesting machine. The elevator 14 can also be adjusted to an elevating mode of operation, as shown in Figure 2, in which the crop can be elevated so as to be able to fall under gravity from the end 20 of the tail portion 17 and into a collecting vehicle 21 located alongside the machine 10. The machine 10 therefore comprises a single piece of agricultural equipment which can operate in the manner of a conventional harvester in order to dig-up crop growing in rows 11 in the ground or to raise crop previously deposited in rows 19, but which can be readily adjusted to operate in either one of the two required modes of operation, namely the lateral deposition mode shown in Figure 1 when air drying of the crop in rows on the ground is required, and lateral elevation when the crop is required to be collected in the collecting vehicle. In the first mode of operation, as shown in Figure 1, the main portion 15 of the elevator is adjusted to a substantially horizontal position, or at a small upward inclination to the horizontal e.g. up to 30°, and the tail portion 17 is pivotally adjusted relative to the main portion 15 so that end 20 is located close to the ground surface, thereby to reduce the distance through which the potatoes fall onto the ground. The adjustment of the main portion 15 and tail portion 17 is also carried out in such a way that the potatoes can be deposited in one of the existing furrows (19) located adjacent to the machine. This existing furrow therefore holds the potatoes while they are being dried, and prior to a further passage of the machine along the furrow in order to pick-up the dried potato. Evidently, as can be seen from Figures 1 and 2, the machine 10 can pick-up two-rows of a growing crop, but will deposit these two rows into a single drying row 19. However, as will be evident from the subsequent description with reference to Figures 4 to 6, the operator of the harvesting machine can follow any required predetermined patterns of movement backwards and forwards over the rows of crops, such that four rows of growing crop can be deposited into a single drying row. The subsequent harvesting of the dried rows of crop will then involve only one quarter of the number of paths of travel required for the initial digging-up of the crop. References 1, 2, 3, 4, 5, 6 used in Figures 4 and 5 denote alternative succesive paths of travel of a single (and repeatable) cycle of operation. Figure 1 shows in full lines the adjusted position of the tail portion 17, to enable the fullest lateral extent of transfer of crop from the machine, but if it is required to deposit the crop in furrows which are nearer to the machine, then the tail portion may be inwardly adjusted so that end 20 overlies any predetermined one of the inner furrows e.g. furrow 22 as shown in Figure 1, with the tail portion 17 being shown in dashed outline. To enable the potatoes to be guided inwardly in this matter, the side 17a of the tail portion 17 may take the form of a piece of canvas, or a guide plate or chute, so that the potatoes can be discharged downwardly and inwardly in a direction towards the machine 10. The main portion 15 of the elevator 14 can be pivoted about horizontal pivot axes at its lower end 16 by means of a ram 23, and tail portion 17 can be pivoted about a horizontal pivot axis 24 relative to the main portion 15 by means of a ram 25. Figure 1 shows the lateral deposition position taken up by the main portion 15, and two alternative positions of the tail portion 17. Figure 2 shows the elevational discharge position of the elevator 14, in which the main portion 15 is pivoted upwardly to an angle of about 60° to the horizontal, and the tail portion 17 is adjusted in such a way so that one part 26 forms a prolongation of the main portion 15, whereas a further part 27 extends substantially horizontally over the upper surface of the collecting vehicle 21 so that gravity discharge can take place. Figures 1 and 2 show three alternative positions of adjustment of the elevator 14, and Figure 3 shows an upwardly and partly inwardly pivoted position of the elevator 14, suitable for transport of the machine. The invention is also concerned with a method of harvesting root crops growing in substantially parallel rows in the ground, with longitudinal spaces defined between adjacent rows over which can travel the wheels of a propelling vehicle and a trailed harvesting machine coupled therewith, and examples of the method are disclosed in Figures 4 to 6. Figure 4 shows one example of a mode of digging-up two adjacent rows of crops at a time with the harvesting machine during each passage of the machine. The elevator 14 is pivoted to the fully extended lateral position, as shown in Figure 1, and the first pass of the machine is shown by reference 1, and during this pass two rows of crops 28 and 29 can be dug-up, separated in the machine 10 from any soil and stones dug-up at the same time and then directed to a discharge station at the rear of the machine adjacent to the elevator 14. The crop obtained from the two rows 28 and 29 is then laterally discharged from the free end of the elevator 14 to fall under gravity into furrows 30. At the end of pass 1, the tractor and harvesting machine carry out a reverse pass in the direction of the arrow 2, which it will be noted is based six rows of crops away from the rows cleared during pass 1. During travel along the reverse pass 2, the two rows of crops 31 and 32 are laterally discharged to form a line of deposited crop 33 in a furrow defined between so far uncleared rows of crops 34 and 35. At the end of pass 2, the harvesting machine 10 then follows a further pass in the direction of the arrow 3, with lateral discharge of the crops as shown by the arrow, and this continues through until a complete cycle up to pass 6 has been carried out. Evidently, as can be seen for furrow 3, this results in a double deposit derived from reverse pass 2 and forward pass 5, and therefore the six passes or lanes of travel 1 to 6 dig up 12 rows of growing crop, and deposit these 12 rows in only three furrows each bearing the product of four rows of growing crop. The crops are then allowed to dry for any required length of time, and then the crop is picked-up by further passes of the harvesting machine, and then discharged, following adjustment of the elevator 15 to the position shown in Figure 2, so that the dug-up and dried crop is collected in the collecting vehicle. Figure 5 shows an alternative pattern of an operating cycle of the machine, in such a way that only two rows of dug-up crops are deposited into each drying row or furrow. Figure 6 shows the manner by which the harvesting machine 10 can be used to pick-up the dried rows of crop, and then discharge the crop (with the elevator 14 raised to the position of the second mode of operation as shown in Figure 2) into a trailer 44 towed behind a propelling vehicle 45.

Claims: A harvesting machine (10) for root crops growing in substantially parallel rows (11) in the ground and which comprises: a wheel-supported frame which is movable over the ground in a direction parallel to said rows (11) with the wheels (13) running in the spaces (12) defined between the rows (11); a digging mechanism (41) at the forward end of the machine and extending laterally by a sufficient extent to enable two adjacent rows (11) of crop to be dug-up at the same time; means (42) provided on the machine for separating the crop from any soil and small stones dug-up at the same time as the crop; means for directing the separated crop to a discharge station (43); and, a discharge elevator (14) pivotally mounted on one side of the machine adjacent to the discharge station (43) via a pivotable mounting (16a) and comprising a main portion (15) mounted at one end (16) on the pivotable mounting (16a) and a tail portion (17) which is pivotally connected to the main portion (15), said elevator (14) being adjustable about said pivotable mounting (16a) in order to vary the height of the discharge end (20) of the tail portion (17) when the elevator (14) is being used in a crop transfer mode of operation to transfer crop from the machine to a collecting vehicle (21) located alongside the machine; characterised in that the main portion (15) and the tail portion (17) are downwardly adjustable from the crop transfer position about the pivotable mounting (16a) so as to take-up a lateral deposition mode for depositing crop in a parallel row alongside the path of travel of the Machine on the ground, and in that the tail portion (17) is adjustable relative to the main portion (15) so that the discharge end (20) of the tail portion (17) can be located close to the ground and at any required lateral spacing from the machine. A harvesting machine according to Claim 1, characterised in that, when the elevator (14) is in the lateral deposition mode, the main portion (15) extends horizontally or is slightly upwardly inclined to the horizontal, and the tail portion (17) extends downwardly of the end of the main portion (15). A harvesting machine according to Claim 2, characterised in that the discharge end (20) of the tail portion (17) is adjustable in a direction laterally inwardly towards the machine so that crop can be discharged into a row (22) located closer to the machine. A harvesting machine according to any one of Claims 1 to 3, characterised in that the tail portion (17) comprises an L-shape as seen in end view, and is arranged such that, when the elevator (14) is in the crop transfer mode of operation, one part (26) of the tail portion (17) forms a continuation of the main portion (15), and another part (27) extends substantially horizontally. A harvesting machine according to any one of Claims 1 to 4, characterised in that the elevator (14) is inwardly pivotable about the pivotable mounting (16a) to an upright inoperative transport position. A harvesting machine according to Claim 3, characterised in that the tail portion (17) has a cover surface (17a) arranged to guide crop to be discharged inwardly. A method of harvesting root crops growing in substantially parallel rows (11) in the ground, with longitudinal spaces (12) defined between adjacent rows over which can travel the wheels of a propelling vehicle and a trailed harvesting machine (10) coupled therewith, the machine having an elevator (14) mounted thereon for discharging the harvested crop via a discharge end (20) of the elevator (14), the method comprising : digging-up two adjacent rows (11) of crop at a time with the harvesting machine during each passage of the machine; separating-out the crop in the machine from any soil and stones dug-up with the crop, and directing the crop to a discharge station (43) in the machine; laterally discharging the crop from the machine via the elevator (14), when the latter is adjusted to a lateral discharge mode in which the discharge end (20) is located close to the ground, to deposit the crop in a row (18) extending substantially parallel to the dug-up rows (11), and while the machine is digging-up the crop in said rows during each passage of the machine; allowing the crop deposited in the row (18) to dry to any required extent; picking-up the deposited crop after required drying using the same harvesting machine (10); and, elevating the crop via the elevator (14) when the latter is adjusted to an elevation mode, so that the crop can fall under gravity into a collecting vehicle (21) located alongside the harvesting machine (10).

Inventors: ROYNEBERG ERLING, ROYNEBERG, ERLING
Applicants: KVERNELAND UNDERHAUG AS
Application year: 1990
Main classification: A01D21
IPC codes: A01D33, A01D51