GB2101462A - Planting machine - Google Patents

Abstract

Seedlings (13) which are to be planted are arranged to be introduced onto a transverse conveyor which delivers them one by one and in a substantially horizontal attitude to respective supporting ledges (64) disposed generally radially around a rotatable wheel (44) which is driven by its contact with the ground. The seedlings are transferred to the ledges (64) when the latter are approximately horizontal and moving downwardly whereby the seedlings slide off the edges to be planted into the ground at regular spaced intervals as the edges become vertical during continued rotation of said wheel. <IMAGE>

Description

SPECIFICATION Planting machine The present invention relates to crop planting machines.

Crops may be established in one of two ways.

They are either established directly in the area in which they are to mature or they are first grown in a nursery area and transplanted.

During the last decade there has been a move to direct establishment; the latter system requires less field labour and is therefore easier to manage.

Direct establishment has, however, a number of disadvantages: 1. The crop occupies the land for longer.

2. The crop is likely to mature later.

3. The crop may be lower yielding.

4. More seed is required.

5. It is less predictable in yield and maturity.

6. Weed control is more expensive.

7. The crop is very vulnerable to damage from birds, pests and diseases in the early stages of establishment.

If a fully automatic transplanting system could be produced which would allow a full plant stand to be established in the field, it is likely that there would be a swing away from direct establishment.

In 1980 the bandolier system was demonstrated by the National institute of Agricultural Engineers. This system was based on two machines. One machine produced a bandolier of paper containers into which seeds for young plants could be established. The other machine cut the tape which joined the individual containers into a bandolier so to allow the machine to plant these containers into the soil at predetermined spacings.

Automatic planting units have evolved following work in Japan and Finland. These are based on the chain pot system of linked paper pots. The paper lattice framework is purchased by the grower, who fills it with a suitable compost and after the plants have been established the automatic planting units feed the plants through the machine in a similar manner to the NIAE system. The disadvantages with both the NIAE and the chain pot system are: 1. It is labour intensive during propagation. The maximum output with the NIAE bandolier is likely to be 12,000 containers per hour. This compares with 40,000 which can be produced by peat block systems.

2. The uniformity of establishment in the bandoliers is dependent upon the seed quality.

3. There is no facility for improving the uniformity of establishment during the propagation stage.

4. The paper lattice lacks strength.

5. The machines at present available for planting are inefficient; their planting speed is slow and they do not have an effective planting mechanism.

The machine to which this invention relates is a planting machine which will allow: 1. Efficient production of seedlings.

2. Full stand in the propagation area and field.

3. Good control of pests and diseases.

4. Is simple.

5. Requires the minimum of labour for field establishment.

In some embodiments, the machine is capable of automatically planting plants grown in celled trays.

In accordance with one aspect of this invention.

there is provided an assembly of rotating ledges which are disposed substantially radially relative to a common axis of rotation such that when items to be planted or otherwise operated on are presented one by one to the ledges when the latter are in a substantially horizontal attitude and moving downwardly, the said items eventually slide off the ledges upon continued rotation of the assembly whereby to be delivered downwardly to the ground or to a further operating stage.

In accordance with a second aspect of the present invention there is provided a planting machine which is adapted to be displaced, for example on the back of a tractor, over ground to be planted, and wherein seedlings are arranged to be introduced onto a conveyor or onto a slide or onto a timed displacement mechanism which delivers them one by one and in a substantially horizontal attitude to respective supporting ledges disposed generally radially around a rotatable structure which rotates at a constant speed in a plane parallel to the direction of displacement of the machine, the seedlings being transferred to said ledges when the latter are approximately horizontal and moving downwardly whereby the seedlings slide off the ledges to be planted into the ground at regular spaced intervals as the ledges become vertical during continued rotation of said structure.

By arranging for the seedlings to form a queue on said conveyor, slide or timed displacement mechanism upstream of the rotating ledges, it can be ensured that every ledge receives a seedling whereby no gaps are left during planting.

Preferably the ledges are disposed on a side surface of a wheel and the conveyor onto which the seedlings are introduced is itself substantially horizontal. The conveyor could, however, be disposed at an angle to the horizontal in some embodiments.

Advantageously the seedlings are contained initially in moulded plastics trays, each of which comprises a number of individual compartments arranged longitudinally of the tray, the trays being supported so as to lie parallel to the conveying direction of the conveyor, and there being provided a plurality of linearly reciprocable pistons, one for each of the compartments of a tray, which are adapted to be projected into or through the bases of the compartments whereby to eject the seedlings onto said conveyor.

The support for the trays can conveniantly be achieved by means of a generally cylindrical holder containing a plurality of longitudinally extending, peripheral slots into which the trays are introduced, the holder being rotatable about a horizontal axis and being periodically indexed whereby the trays are successively brought to an ejecting station at which the piston are disposed.

Preferably, when at said ejecting station, the trays are in a substantially horizontal attitude, but with their mouths facing slightly upwardly whereby the pistons cause the seedlings to be ejected at a corresponding small positive angle to the horizontal, the conveyor being arranged to lie slightly below the mouth of the tray from which the seedlings are being ejected.

If the assembly is then being moved forwardly at a constant speed, the said items will be presented to the ground at regularly spaced intervals.

The invention is described further hereinafter, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a plan view of one embodiment of a planting machine in accordance with the present invention; and Fig. 2 is a sectional side view of the embodiment of Fig. 1, taken on the line Il-Il of Fig. 1, and showing the passage of seedlings through the machine during operation.

The illustrated machine is specifically adapted to plant small seedlings which have been propagated in plastics trays 10, each of which trays comprises a plurality of separate compartments containing individual seedlings 11.

Thus, each tray compartment contains a single seedling 11 together with an associated block 1 3 of growing composition (normally a peat/sand mixture) which will be referred to hereinafter simply as a "soil" block. The seedling trays 10 can be similar to the conventional type of flangelipped trays currently used for the retail sale of bedding plants and vegetable seedlings. One difference, however, is that the base of each individual compartment in the present tray is either weakened in a central region or is apertured, for a reason which will become apparent below.

To suit the particular embodiment of planting machine illustrated in the drawings, the trays 10 each have five compartments. The latter number could, however, be greater or smaller in other embodiments depending on the width of the machine and the required planting speed, but five is probably a convenient number in practice. The trays 10 are inserted into respective longitudinally extending slots 12 formed in the periphery of a generally cylindrical tray holder 14 (see Fig. 2), the slots 12 being defined between adjacent pairs of a plurality of radically directed plates 1 6 which are welded at their ends to respective circular end plates 18, 20 so as to extend radially inwardly of the periphery of the cylindrical holder 14.The centre of the end plate 20 is welded to a perpendicularly extending shaft 22 which is journalled in bearings 24, 26 on a main frame 28 whereby the end plate 20, and hence the tray holder 1 4 as a whole, is rotatable about the horizontal axis defined by the shaft 22. The end plate 18 is in the form of an annular disc whose inner periphery is guided by one or more (preferably three) guide rollers (not shown) which are rotatably mounted on the frame 28 so as to provide an outboard support for the cantileverjournalled tray holder 14.

The trays 10 are introduced to the holder 14 when the slots 12 are in their uppermost (i.e. 12 o'clock) position, or approximately in this position.

The trays 10 may be introduced manually, one by one, directly into the holder 14. In other embodiments a flexible web can extend around both the holder 14 and a further cylinder or roller (not shown) positioned to the right of the holder 14 (as viewed in Fig. 2), the web containing a plurality of apertures which are arranged to line up with the slots 1 2 in passing around the holder 14.

The trays can then be introduced automatically or manually into the web at a location upstream of the holder 14 whereby they are carried by the web to the holder where the trays automatically enter the slots as they reach the periphery of the holder.

The cylindrical holder 14, into which the seedling-containing trays have been inserted, is arranged to be indexed at regular intervals in angular steps corresponding to the circumferential length of one slot 12. Two can be achieved by any suitable indexing arrangement. In the presently illustrated embodiment, indexing is performed by way of a constantly rotated shaft 30 carrying a single tooth 32 which meshes with the plates 1 6 during part of each of its revolutions so as to engage and angularly displace one plate through the required distance.During the majority of the revolution of the shaft 30, however, the tooth 32 is out of engagement with the plates 1 6 so that the tray holder 14 is stationary, its position then being held fixed by a spring-biassed pawl (not shown) which engages between a pair of adjacent plates 1 6.

The constant speed drive for the shaft 30 is achieved by way of chains 34 and 36 from a horizontal shaft 38 which isjournalled in bearings 40, 42 on the frame 28 and is rigidly connected to a ground wheel 44 which lies in a plane extending lengthwise of the machine. As best shown in Fig.

2, the frame 28 is adapted to be suspended from a conventional tractor hitch lift (not shown) whereby the ground wheel 44 engages the ground so as to be driven clockwise as viewed in Fig. 2 when the frame is drawn in the direction of arrow A. To assist in minimising slip between the wheel 44 and the ground, the wheel 44 is provided with a plurality of laterally extending, radially inwardly directed fins 46 on its left-hand side as viewed in Fig. 1.

As will be evident from Fig. 2, a lowermost portion of the periphery of the ground wheel 44 extends slightly below ground level into a furrow produced by a plough blade, or blades 48 suspended from the frame 28 upstream of the wheel 44.

For the purpose of removing the seedling from the trays 10, there is mounted at an ejecting station within the cylindrical tray holder 14 an arrangement of five pistons 50 (one for each compartment of the trays) which are linearly reciprocable in an approximately horizontal plane by means of a crank mechanism driven by the chain 36 from the shaft 38. The pistons are rigidly connected to a transversely extending bar whose ends are slidably received in elongate stationary guides which are fixed relative to the frame 28.

The bar is coupled by pivotable links to a crankshaft 52 which is journalled on the frame 28 and driven at constant speed by way of the chain 36.

This mechanism is shown only diagrammatically in Fig. 2 for the purposes of illustration.

The function of the pistons is (as illustrated in Fig. 2) to be displaced repeatedly in synchronism with the indexing of the tray holder 14 so as to project into that one of the slots which is currently occupying a predetermined substantially horizontal position whereby the pistons extend through the apertures in the bases of the various compartments of the tray occupying that position so as to engage and eject the seedlings from those compartments. It is essential, of course, that this ejecting action of the pistons occurs only when the tray holder 14 is stationary and the timing of the piston movement is selected accordingly.

Advantageously, the slot into which the pistons are projected is arranged to occupy a position as shown in Fig. 2 whereby the mouth of this slot, and the tray contained therein, is directed slightly upwardly relative to the horizontal so that the seedlings, in being ejected from the tray compartments by the pistons, are caused to adopt a trajectory which results in them coming to rest substantially horizontally on the upper run of a conveyor 54. The conveyor 54 extends horizontally in a direction transverse to the frame 28 and perpendicular to the plane of the ground wheel 44, the conveyor comprising a flexible belt which extends around pulleys rotatably mounted on the frame 28. The conveyor 54 is driven from the shaft 38 via a chain 56, gears 58, 60 and a shaft 62.Preferably, the belt is internally toothed to enable it to be positively driven without slip for conveying seedlings, deposited thereon by means of the pistons, in the direction of arrow B towards the ground wheel 44.

Thus the operation of the pistons 50 is such that each time a full tray carried by the holder 14 reaches the horizontal position, the five pistons are displaced into the associated slot 1 2 whereby to project through the apertures in the bases of the individual tray compartments, engage the bases of the soil blocks 1 3 in these compartments, and eject the latter soil blocks 13 and the seedlings 11 contained therein so that they land on the conveyor 54 (see Fig. 2) with their lateral separation substantially maintained.

The moving conveyor 54 carries the seedlings towards the ground wheel 44. This wheel is provided on its side surface facing the conveyor 54 with a plurality of angularly spaced apart, generally radially directed rectangular ledges 64 of width slightly greater than the width of the soil blocks 1 3 of the seedlings 11. Advantageously, these ledges 64 are formed by metal plates welded so as to extend perpendicularly to the plane of the wheel 44, each plate having a triangular portion 65 bent at right angles to it so as to form an edge 66 which again extends generally radially of the wheel axis but leads the associated ledge 64 in the direction of rotation of the wheel 44.In fact, the ledges 64 are not necessarily strictly radial but are arranged such that they lie parallel to the conveying surface of the conveyor 54 when they move past the downstream end of this conveyor. By virtue of this arrangement, when each seedling on the conveyor reaches the ground wheel it is passed smoothly onto one of the ledges 64 as this moves downwardly past the end of the conveyor, the depending triangular portion 65 of the next ledge 64 then moving down to prevent the next seedling leaving the conveyor until the succeeding ledge has arrived to take up its position parallel to the conveyor when it can receive its seedling. Thus, the seedlings are transferred one by one to the ledges 64 as these move past the downstream end of the conveyor 54.

As illustrated in Fig. 2, the seedlings rest on the ledges 64 while the wheels move through approximately 900 whereupon the seedlings slide downwardly along the ledges and drop into the furrow formed by the plough 48. By virtue of the shape of the metal plate forming the ledges and the forward movement of the wheel 44, the ledges do not interfere with the deposited seedlings in moving upwardly during the succeeding 900 rotation. A device (not shown) is provided at the trailing end of the frame to fold over the edges of the furrow to leave the seedlings firmly planted in the ground 70.

Although not shown in the drawings, there is preferably provided a frame arrangement for holding the trays 10 in place in the tray holder 14 during their carriage to the seedling ejecting station. Conveniently this frame can comprise a plurality of curved rods fixed to the frame 28 and, extending (in an anticlockwise direction as viewed in Fig. 2) circumferentially around the cylindrical holder 14 and slightly above it from approximately the 12 o'clock position to just below the uppermost edge of a tray 10 when the latter is at the ejecting stat: Jn. The lowermost ends of these curved rods thus acts as a stop for the upper edge of the tray during ejection of the seedlings by the pistons.The lower edge of the tray during this operation abuts a fixed plate 70 lying between the tray holder 14 and the conveyor 54 so as to provide a positive stop for the top and bottom edges of the tray during seedling ejection.

The curved rods also serve to separate the foliage of the individual seedlings during conveyance in the holder 1 4.

The conveyor preferably has an associated guide plate 72 extending perpendicularly to the wheel 44 to assist in retaining the seedlings on the conveyor and a stop plate 74 upstream of the ejection region.

The conveyor can, where necessary, be provided also with a means for straightening up the seedlings on the conveyor prior to their transference to the ledges on the ground wheel.

Such means would take the form of a loosely pivoted flap freely suspended over the downstream end of the conveyor so as to pivot about a horizontal axis perpendicular to the conveying direction. The weight of the flap is chosen to suit the nature of the seedlings being handled so that in engaging and passing under the flap the seedlings are caused to be straightened up on the conveyor so as to ensure that they lie perpendicular to the conveying direction. An alternative arrangement could comprise a similarly suspended flap but one which is released for free pivoting movement only after the pistons have been withdrawn from a given ejection operation.

In this way the seedlings initially encounter a fixed barrier to their progress on the conveyor which positively aligns them in the direction perpendicular to the conveying direction prior to allowing them to pass when released to become freely pivotable.

As shown in Fig. 2, on continued rotation of the tray holder 14, the empty trays 10 eventually drop out of the slots 12. In practice, a means (not shown) is provided for collecting and removing such empty trays, such means comprising for example, a further transverse conveyor disposed beneath the holder 1 4.

It will be appreciated that the ground wheel and conveyor arrangement described above has many other agricultural uses besides planting seedlings.

For example, if in place of the tray holder 14 there is provided a supply hopper for, for example seed potatoes, and if the conveyor 54 is reduced in width to a size comparable to that of the largest potatoes to be planted or if the conveyor is replaced altogether by some means for presenting potatoes one by one to the ledges on the ground wheel, then a means is provided for introducing seed potatoes one by one to the ground at predetermined regular intervals which are substantially independent of the planting speed.

Another use of the ground wheel configuration is in carrot-topping where the foliage of carrots is to be removed. The ground wheel in this case would not be driven by contact with the ground but would be driven by, for example, a separate motor. Carrots would be arranged to be presented to the wheel one by one by a suitable feed device and the carrots would then be carried separately by the ledges 64 to a suitable cup-shaped holder beneath the lowermost part of the wheel where the carrot tops would be severed by a moving knife device.

In other embodiments it may be preferred to replace the crank driven pistons with a plurality of individual pistons each of which is associated with a respective pneumatic or hydraulic power cylinder, for example a plurality of midget air cylinders. These would be operated singly or in groups. Such devices would cause the pistons to have much more rapid forward and retraction strokes resulting in an improved ability to efficiently eject the seedling blocks.

In a further embodiment, the interconnected piston arrangement shown in the present drawings could be retained but be driven by one or more pneumatic or hydraulic power cylinders instead of by the illustrated crank mechanism.

In a still further embodiment, the conveyor 54 is not driven at a constant speed but is adapted, for example by internal toothing, to be driven in a stepped fashion so that when it receives the seedlings ejected by the pistons it is stationary and is only advanced inbetween such ejection operations.

Claims (20)

1. A planting machine comprising an assembly of rotating ledges which are disposed substantially radially relative to a common axis of rotation such that when items to be planted or otherwise operated on are presented one by one to the ledges when the latter are in a substantially horizontal attitude and moving downwardly, the said items eventually slide off the ledges upon continued rotation of the assembly whereby to be delivered downwardly to the ground or to a further operating stage.

2. A planting machine as claimed in claim 1 wherein the ledges are formed by respective plates attached to the side of an upright wheel so as to extend perpendicularly to the plane of the wheel.

3. A planting machine as claimed in claim 2 wherein each plate has a triangular portion bent substantially at right angles to it so as to form an edge which also extends generally radially of the wheel axis but which leads the associated ledge in the direction of rotation of the wheel.

4. A planting machine as claimed in claim 2 or 3 wherein the wheel is a ground wheel which is mounted on a frame and which rotates by virtue of its contact with the ground when the frame is caused to be moved over the ground

5. A planting machine which is adapted to be displaced, for example on the back of a tractor, over ground to be planted, and wherein seedlings are arranged to be introduced onto a conveyor or onto a slide or onto a timed displacement mechanism which delivers them one by one and in a substantially horizontal attitude to respective supporting ledges disposed generally radially around a rotatable structure which rotates at a constant speed in a plane parallel to the direction of displacement of the machine, the seedlings being transferred to said ledges when the latter are approximately horizontal and moving downwardly whereby the seedlings slide off the ledges to be planted into the ground at regular spaced intervals as the ledges become vertical during continued rotation of said structure.

6. A planting machine as claimed in claim 5 wherein the ledges are formed by respective plates attached to the side of an upright wheel so as to extend perpendicularly to the plane of the wheel.

7. A planting machine as claimed in claim 6 wherein each plate has a triangular portion bent substantially at right angles to it so as to form an edge which also extends generally radially of the wheel axis but which leads the associated ledge in the direction of rotation of the wheel.

8. A planting machine as claimed in claim 6 or 7 wherein the wheel is a ground wheel which is mounted on a frame and which rotates by virtue of its contact with the ground when the frame is caused to be moved over the ground.

9. A machine as claimed in claim 5, 6, 7 or 8 wherein the seedlings are arranged to form a queue on said conveyor, slide or timed displacement mechanism upstream of the rotating ledges, so as to ensure that every ledge receives a seedling whereby no gaps are left during planting.

10. A machine as claimed in claim 9 wherein the conveyor onto which the seedlings are introduced is itself substantially horizontal.

11. A machine as claimed in claim 9 wherein the conveyor onto which the seedlings are introduced is disposed at an angle to the horizontal.

12. A planting machine as claimed in any of claims 5 to 11 wherein the seedlings are contained initially in moulded plastics trays, each of which comprises a number of individual compartments arranged longitudinally of the tray, the trays being supported so as to lie parallel to the conveying direction of the conveyor, slide or timed displacement mechanism and there being provided a plurality of linearly reciprocable pistons, one for each of the compartments of a tray, which are adapted to be projected into or through the bases of the compartments whereby to eject the seedlings onto said conveyor.

13. A planting machine as claimed in claim 12 wherein the support for the trays is achieved by means of a generally cylindrical holder containing a plurality of longitudinally extending, peripheral slots into which the trays are introduced, the holder being rotatable about a horizontal axis and being periodically indexed whereby the trays are successively brought to an ejecting station at which the piston are disposed.

14. A planting machine as claimed in claim 13 wherein, when at said ejecting station, the trays are in a substantially horizontal attitude, but with their mouths facing slightly upwardly whereby the pistons cause the seedlings to be ejected at a corresponding small positive angle to the horizontal, the conveyor, slide or timed displacement mechanism being arranged to lie slightly below the mouth of the tray from which the seedlings are being ejected.

1 5. A planting machine as claimed in claim 13 or 14 including a flexible web extending around said cylindrical holder and around a further cylinder or roller, the web containing a plurality of apertures which are arranged to line up with the slots in passing around the holder, the arrangement being such that trays introduced into the web apertures at a location upstream of the holder are carried by the web to the holder where the trays automatically enter the slots as they reach the periphery of the holder.

1 6. A planting machine as claimed in claim 13, 14 or 1 5 including a frame arrangement for holding the trays in place in the holder during their carriage to the location of ejection.

17. A planting machine as claimed in claim 16 where the frame arrangement comprises a plurality of curved rods extending radially outwardly of and circumferentially around a portion of the cylindrical holder, the one ends of the rods acting as a stop for the upper edge of each tray during ejection of the seedlings by the pistons.

18. A planting machine as claimed in any of claims 5 to 1 7 where the conveyor, slide or timed displacement mechanism is provided with a means for straightening up seedlings prior to their transference to the ledges.

1 9. A planting machine as claimed in claim 18 where the straightening up means comprises a loosely pivoted flap freely suspended over the conveyor, slide or timed displacement means so as to pivot about a horizontal axis perpendicular to the conveying direction.

20. A planting machine substantially as hereinbefore described with reference to the accompanying drawings.