GB2028626A - Mobile harvester - Google Patents

Abstract

The harvester has a number of picking elements (18) arranged to move up a path which is downwardly inclined in the forwards direction of the machine. By suitably relating the upward speed of the picking elements with the forward speed of the machine, the elements can be made to move vertically upwards through the branches of the fruit-bearing plants to be harvested. The picking elements may be arranged in two groups, one group being along one side of a row of plants to be harvested and the other group being along the other side of said row. Adjustment means may be provided to alter the distance separating these groups. The picking elements may take the form of elongate elements or rotating brushes. The harvester is suitably provided with means to vibrate the plant local to the picking element either directly by the elements or by a conventional vibrator. <IMAGE>

Description

SPECIFICATION Improvements in and relating to mobile harvester machines The present invention relates to mobile harvester machines and in particular, but not exclusively, to mobile apple harvesters.

Up to now, the only apple harvesting equipment adopted commercially to any significant extent has been the shake and catch equipment designed to shake individual limbs of the trees or their trunks and to catch any apples dislodged before they hit the ground.

Because a significant proportion of the apples are bruised either before or during catching however, this prior equipment has, as far as is known, been used only for harvesting apples destined for processing. A satisfactory means for mechanically harvesting apples for the fresh fruit market has not yet been developed and it is an object of the invention to provide a mobile harvester machine that can be utilised for this purpose.

According to the present invention, a mobile harvester machine for harvesting fruit from a row of fruit-bearing plants comprises a plurality of picking elements adapted during operation of the machine to move upwardly through the plants with at least root portions of the picking elements moving relative to the machine body up a path that is inclined downwardly in the forwards direction of the machine.

The machine preferably includes drive means arranged to move the picking elements up the path with a component of motion parallel to the ground that is substantially equal and opposite to the motion of the machine along the ground so that, in operation of the machine, the picking elements move substantially vertically upwards through the plants, i.e. within 5 degrees of the vertical.

It is envisaged, however, that in some cases it may be desirable to operate the machine so as to have the picking elements passing upwardly through the plants at significantly greater angles to the vertical but probably at not more than 45" either side of the vertical.

As the motion of the picking elements through the plants is at least in part dependent on the speed of the machine over the ground, the machine conveniently includes control means adapted automaticalliy to vary the speed of the picking elements in response to changes in the ground speed of the machine whereby the desired motion of the picking elements through the fruit-bearing plants is maintained within acceptable limits.

The control means conveniently comprises a fluid metering unit responsive to changes in the ground speed of the machine to macivary the fluid flow to one or more fluid motors used to drive the picking elements relative to the machine body.

Conveniently the control means includes a transducer driven by one of a number of ground wheels supporting the machine or by an additional ground wheel. Alternatively the fluid flow to the or each fluid motor might be controlled by a valve driven by a mechanically, electronically, or, for example, optically-operated plant sensor or by a valve that is manually controlled with the operator estimating the changes in element speed required to compensate for changes in the ground speed of the machine.

A different approach that might be used would be to sense the motion of the picking elements relative not to the machine body but to the ground andthen to control the ground speed of the machine accordingly.

In a preferred embodiment, the machine is designed to straddle the rows of fruit-bearing plants and the picking elements are arranged to be some on one side and some on the other side of the row during operation of the machine.

Conveniently in this case, the machine includes adjustment means for varying the separation of the picking elements on one side of the row from the picking elements on the other side of the row.

In one such embodiment, the machine body is formed as two interconnected sections, one associated with the picking elements on one side of the row and the other with the picking elements on the other side of the row, the width of the machine being adjustable by varying the positions of the two sections relative to one another.

Conveniently in the straddle version of the machine the ground wheels on one side of the machine can be steered independently of the ground wheels on the other side of the machine and the width of the machine can be varied at will by steering the ground wheels on the one side of the machine in a different direction to the ground wheels on the other side of the machine.

The picking elements should preferably be resilient to reduce or prevent damage to fruit and plants during picking.

Conveniently, each picking element is an elongate element with the length of the elements chosen to suit the size of plant involved and the stiffness chosen to cope with different varieties of plant.

In a machine designed for apple harvesting, each picking element comprises a rigid or semi-rigid core member (e.g. a glass-reinforced polymer rod), surrounded by a layer of highly resilient material (e.g.

polyester foam) provided with a protective outer layer (e.g. an elastomer skin).

It is envisaged that there may in some case be advantage in varying the stiffness of the elements along their length e.g. in the above embodiment by tapering the core member towards the distal end of the element.

It is greatly preferred that the picking elements should be positioned sufficiently close together so as themselves to present a support surface for the picked fruit. In one such embodiment, the picking elements present an inclined support surface along which the picked fruit can roll or slide towards the root portions of the elements and on to or in to an appropriate collection and/or transport device (e.g. a conveyor belt) provided at or adjacent said root portions.

The elongate elements conveniently take the form of rod-like elements which may be curved upwardly at their distal ends e.g. in a 45 degree arc, to encourage picked fruit to roll or slide on to the support surface provided by the elements.

In preferred embodiments, this upturned end portion of the rod-like elements terminates in a relatively stiff end part that is to say in an end part which is stiff relative to padding on the element but flexible relative to its core portion. The function of this end portion is to reduce or resist the local downwards depression of the element that might otherwise occur at the distal end of the element during picking. In the absence of these end parts, there would be a tendency for the picked apples to roll or slide off the ends of the elements over the locally depressed regions rather than along the elements towards their root portions.

The picking elements may if desired be arranged to have the root portions of at least some of the picking elements deliberately misaligned to discourage fruit from rolling or sliding over successive elements to the front of the machine, the elements thereby loosely defining channels leading from the distal ends of the elements towards their root portions.

The root portions of the elements are preferably carried by carriages mounted to run on appropriate guide rails on the machine body. If desired two or more banks of elements may be mounted on each carriage.

Conveniently the carriages are interconnected to form a continuous chain of carriages and in one such case this carriage chain is arranged to be driven by a sprocket wheel e.g. engaging with abutments presented by the various carriages.

It is envisaged that for some fruit it may be possible, as an alternative, for the picking elements each to take the form of one or more rotating brushes.

It will be appreciated that the inclined path for the picking elements need not necessarily comprise a single inclined pathway extending over the fruitbearing sections of the plants. It could for example take the form of two or more inclined pathways arranged e.g. to overlap one another in the vertical sense, so that together the various pathways span the fruit-bearing sections of the plants.

With a single pathway machine, the pathway inclination will usually be between 25 and 35 to the ground surface (e.g. typically 30 ), values less than 70" being preferred and preferably less than 45 .

Where the single pathway is replaced by two or more pathways, these angles will be correspondingly less e.g. typically 10 to 200 for a two pathway machine.

It is envisaged that it may be advantageous to vibrate the plants local to the picking elements either directly by the elements or by a conventional vibrator. This should aid fruit detachment and it should also ease the passage of the picking elements through the branches.

It is further envisaged that it may also be advantageous to mount a conventional vibration device at the rear of the machine e.g. a substantially horizontal finger wheel, to shake off any fruit not previously removed by the picking elements.

A resilient fruit-catching surface is preferably also provided e.g. at the bottom of the machine, to catch fruit knocked off but not caught by the picking elements, and if present, by the conventional vibration device at the rear of the machine.

Conveniently the fruit-catching surface is provided by one or more fruit-catching members at the bottom of the machine.

Preferably, the or each fruit-catching member comprises a flexible sheet suspended beneath the picking elements. The sheet or sheets may slope down towards a conveyor surface so as to deliver to said conveyor surface fruit caught by the fruitcatching members.

Conveniently, the or at least one said fruit-catching member is biased towards a position in which, in operation of the machine, it will engage the trunk or stem of the fruit bearing plant on which the picking elements are currently operating.

In preferred embodiments of the machine, it is provided, at its front end, with one or more branchlifting devices adapted, in operation of the machine, to lift the branches of the fruit bearing plants on which the machine is to operate.

Conveniently the or each branch lifting device comprises a ground skid with two upwardly inclined elongate members.

The machine may also include a bin handling equipment comprising bin-lifting means arranged to swivel about an axis lying perpendicularly to the ground surface and a rotary fruit spreader positioned so as in operation of the machine to transfer fruit from the upper end region of said inclined path to a bin removable by said bin-lifting means. The bin-lifting means may, for example, comprise a fork lift device.

Conveniently, the fruit spreader comprises a plurality of flexible fruit-receiving members partly overlapping one another in a diaphragm-like construction, the rotation axis of the spreader coinciding with an axis of symmetry of said construction lying substantially perpendicular to the plane or planes of the fruit-receiving surfaces.

According to another aspect of the invention, a method of continuously harvesting fruit from successive plants in a row of fruit-bearing plants comprises moving picking elements up a path that is inclined downwardly in the overall direction of harvesting with the component of motion of the picking elements parallel to the ground surface opposite to the overall direction of harvesting and of a magnitude such that the picking elements move substantially vertically upwards through the plants, i.e. within 5 degrees of the vertical.

The invention also includes such a method when utilising a mobile harvester machine according to the present invention.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a general perspective view of an apple harvester machine with some parts omitted and others simplified for clarity; Figure la shows a detail of a fruit conveyor used in the machine; Figure 2 shows a side view of one of the picking fingers used in the machine; Figure 3 shows a detail of a support carriage for the fingers and of guide rails for the carriage; Figures 4to 6 show an end view, a side view and a plan view of the support carriage; Figure 7 shows a plan view of a driving sprocket for the support carriages; Figure 8 is a side sectioned view of the sprocket; Figure 9 shows how the sprocket engages with support carriages; Figure 70 is a circuit diagram for the hydraulic power circuit of the machine;; Figure 11 shows a wheel-levelling mechanism controlled by the circuit of Figure 10; Figure 12 is diagrammatic side view of a first system for unloading fruit from one of the fruit conveyors used in the machine; Figure 13 and 14 are somewhat diagrammatic end views of alternative designs of locking mechanism for clamping together two interconnected sections of the machine; Figure 15 is a circuit diagram for the hydraulic steering circuit of the machine; Figure 16 is a general perspective view of an alternative system for unloading the fruit; Figure 17 is a simplified and partly schematic perspective view of bin-handling equipment for mounting atthe rear end of the machine;; Figure 18 is a simplified and partly schematic perspective view of an assembly of fruit-catching members for mounting beneath the array of fruit picking elements; Figure 19 is a simplified and partly schematic end view of the assembly of Figure 18; and Figure 20 is a partly schematic perspective view of a branch-lifting device for mounting at the front end of the machine.

Thus referring first to Figure 1, the drawing shows a front perspective view of an apple harvester machine 10 designed to straddle a row of apple trees (not shown).

In essence the machine comprises two picking assemblies (partly shown at 12), two conveyors (one shown at 14), and two platforms 15 intended to support collection bins (not shown) at the rear f the macine.

Each picking assembly 12 comprises a plurality of elongate picking elements on fingers 16 (Figure 2) positioned sufficiently close together to provide a sidewardly inclined support surface along which the picked fruit can roll or slide towards the associated conveyor 14. Each finger 16 comprises a "fibre glass" (i.e. glass-reinforced polymer) rod core mem ber 18 surrounded by a layer of polyester foam 20 with an elastomer skin 22 acting as a protective sheath for the foam. In Figure 1 only the core members 18 have been shown for clarity.

For the apple harvester machine shown in Figure 1, the length for the straight portion of the fingers was chosen at 360 mm and the stiffness of the core member 18 was chosen so that with the exposed root portion 23 of the core clamped in a finger holder as will hereinafter be described, a load of 20 kgf applied as indicated at "L" in Figure 2 will produce a core deflection of between 65 mm and 85 mm.

The highly resilient nature of the fingers not only prevents the apples being bruised during picking, but it also reduces the chance of fruit buds, branches or spurs being damaged as the fingers move through the branches of the trees.

At their distal ends, the fingers 16 are each provided with an elastomer moulding bonded to the fibre glass rod to form an end part 24 whose function is to provide a relatively stiff portion which will encourage the apples to roll or slide onto the more resilient parts of the finger. Without parts 24, the ends of the highly resilient fingers 16 would tend to depress under the weight of the picked apples and this would introduce a tendency for the picked apples to fall off the ends of the fingers to the ground.

It will be noted that end parts 24 are capable of deflection (as illustrated by the alternative position 24' in Figure 2) should they contact a rigid or semi-rigid obstruction such as a branch.

To encourage the apples to move along the fingers and to reduce further the likelihood of the apples falling off the ends of the fingers once picked, the free end region (25) of each finger is curved upwardly from its straight portion (26) over a 45 degree arc as shown in Figure 2.

The fingers are arranged in groups of three with each group attached via finger-holders to its own carriage. One such carriage 28 is shown in Figure 3 to 6 and, as may be seen from these Figures, the holders (29) hold the fingers at an angle such that the straight portions 26 of the fingers will slope sidewardly, typically at 150 (Figure 4) to provide the sidewardly inclined support surface for the apples.

Moreover, the holder 29 for one of the three fingers in each group (the left-hand finger in Figure 5) is deliberately misaligned. This misalignment results in the fingers providing lateral "channels" loosely "defined" by the three fingers of each group and the adjacent misaligned finger of the next group. These channels discourage the apples from rolling or sliding towards the front of the machine over successive fingers in the assembly. Each of the carriages 28 is mounted on five wheels 30-34 (Figure 5), designed to run over a closed path defined by inner guide rails 36,37 (Figure 1), and sprocket 39, outer guide rails 41,42, and front guide bars 44, 45.

Returning again particularly to Figures 4 - 6, it will be seen that each carriage comprises a C-shaped framework (Figure 5).

The weight of the carriage is supported by the two wheels (30,31) mounted on support blocks 46 and 47 at the top of this framework. These wheels run along support surfaces in the top guides 36. One such surface (48) is shown in Figure 3. It will be noted that the support surface 48 is of course interrupted to allow passage of the upright 50 of carriage 28. The three remaining wheels 32 - 34 (Figure 5) rotate about axles arranged perpendicularly to the horizontal axes of the support wheels 30, 31 and engage with upright surfaces of the guides to discourage excessive lateral movement of the carriage.

Although the lower limb 52 and the upright 50 of the carriage framework are of hollow beam construction, the top limb of the carriage is preferably provided by two plates 54, 56 spaced apart by studs 58 and by the root portion of a tongue member 60 which projects rearwardly of the upright limb 50. It is to be understood that the corresponding tongue member of the previous carriage (not shown) projects between the plates 54, 56 where it is secured in place by a clevis pin (at 62) to link the carriages together in a chain formation.

At the top of the apple-picking part of its path each carriage in the chain will leave the guides 36,37 to be engaged by the specially designed teeth of the drive sprocket 39 shown in simplified form in Figure 1 but in detail in Figures 7 to 9. As may be seen from this latter group of Figures, the drive sprocket is polygonal rather than circular and laterally spaced tooth members 64, 65 are secured by brackets 66 to opposite faces of the sprocket wheel at the apices of the polygonal shape. The straight edge portions of the wheel support L-shaped members 68.

As may best be seen from Figure 9, the tooth members 64, 65 span the plates 54, 56 with the top member 65 engaging with wheel support blocks 46 but clearing the (smaller) wheel support blocks 47. In addition the L-shaped members 68 engage the underneath of plate 56 and the sides of both plates 54 and 56.

After leaving the sprocket, the carriages will be taken up by guide rails 41,42 for their return to the front end of the machine.

The sprocket wheels 39 are driven by hydraulic motors designed to rotate them in a sense such that when viewed in plan, and looking towards the front of the machine, the left-hand carriages will move clockwise over their path and the right-hand carriages will move anticlockwise. This means that during the apple-picking part of their travel, the various fingers will all move relative to the machine body up a path (defined by guides 36,37) that is inclined downwardly in the forward direction of the machine 10 and this is an important operational feature of the machine.

In order to achieve the desired motion of the fingers 16 through the branches of the trees for different forward speeds of the machine 10, it is useful to have the motion of the fingers relative to the machine automatically correllated with the motion of the machine along the ground.

With this end in view, a speed sensor ground wheel 70 (Figure 1) is used to drive a hydraulic metering unit in the same hydraulic circuit as the sprocket motors. The main hydraulic circuit for the harvester is shown in Figure 10 where reference numerals 70,72,74, 75 respectively indicate the speed sensor wheel (as before), the hydraulic metering unit and the two sprocket motors. Conveniently, for example the unit 72 could be an open centre, non-reactive hydrostatic steering unit, e.g. a Danfoss OSPB steering unit.

Hydraulic power is provided by a diesel engine 76 (shown also in Figure 1) driving a tandem fixed delivery pump 78 and a variable delivery pump 80.

Oil for the two pumps is taken from a tank 81 via filters 82, 83 and may be returned there via a pressure-relief valve 84 when conditions dictate.

Reference numeral 85 indicates a second pressure valve.

Pump 80 supplies oil to the two wheel-drive motors 86, 87 (for the rear ground wheels) via a crossline relief valve 88. By varying the oil delivery from this pump (by manual control) the machine operator can set the speed of the harvester anywhere from full reverse to full forward.

One half of pump 78 supplies oil to the two sprocket motors 74, 75 via the metering unit 72 and a rotary flow divider 89 with relief valve block 90. The unit 72 regulates the flow of oil to the flow divider in proportion to the forward speed of the harvester as sensed by the wheel 70. The flow divider splits the flow into two equal parts to be fed to the sprocket motors. A third part of the flow can be used to drive a third gear type metering unit in the divider which is mechanically connected to the two main metering units causing them to be driven partly as gear pumps. This provides a greater oil pressure to the motors than can be tolerated by the unit 72.

The other half of pump 78 supplies oil for the fruit conveyor motors 92,94 and levelling rams 96 - 99.

The pump output is split by the flow divider 100 with a relief valve block 101. One branch is fed to a valve 102 which operates the motors 92,94 while the other is fed to valves 104 - 107 which operate the levelling rams. The speed of motors 92,94 is controlled by a flow control valve, manually operated, 108, so that the speed of the fruit conveyors may be set as required.

The rams 96 - 99 are attached to the suspension units of each ground wheel as shown by way of example in Figure 11. Referring both to Figures 1 and 11 it can be seen that ground wheel 118 is mounted on a parallel linkage 120 comprising an upright structural member 121 (not shown in Figure 11) on which are pivoted the upper and lower suspension arms 122, 124. The arm 122 carries upstanding lugs 126 providing a pivot support for the rod 128 of levelling ram 96.

The arms are extended by the members 132, 133 angled away from the centre line of the harvester to give adequate wheel clearance as the wheels are steered. Blocks 136, 138 are pivotally attached to these extensions so that they are free to swivel about axes parallel to the pivot axes of arms 122,124 on the upright 121.

Mounted between these blocks 136, 138 is a kingpin 140 carrying the stub axle 142 on which the ground wheel 118 is mounted. The kingpin is free to swivel in blocks 136,138 so that the wheel may be steered. A short steering arm 144 is also attached to the kingpin and is actuated by the steering cylinder 146. Conveniently the cylinder 146 is swivel mounted on a bar 148 pivoted between the arms 122, 124 so that changes in steering angle as the suspension height is changed are minimized.

Returning now to Figure 1, the basic arrangement is completed by the two conveyor belts of which only one (belt 14) is shown in simplified form in Figure 1. A more accurate view of a section of the belt is given in Figure 1a which is to an enlarged scale. Thus referring to Figure 1a, and, where appropriate, also to Figure 1, it will be seen that each belt comprises a plurality of flights 172 backed along the outside edge of the belt by a flexible wall section 174 which is normally sufficiently slack for it to be able to accommodate any stretching effects taking place as it passes over top and bottom support rollers 176, 177.

The flights 172 are inclined across the width of the belt to encourage apples received from the fingers 16 to roll or slide down to the outside edge of the belt where they will of course be stopped by wall section 174. In this way the inside edge region of the belt is kept free of apples so that there is little or no danger of apples from the fingers being rejected by the belt simply because there is unsufficient space to accept them there.

Atthe upper end of the machine, the top run of the conveyor leads into an unloading assembly (shown in Figure 12) before returning as the bottom run of the conveyor to the bottom support roller 176. This unloading assembly comprises a decelerator 178, a collection bin 180 supported on surface 15 (shown also in Figure 1), and a control system 182 designed to ensure that the decelerator discharges directly on to the topmost apples of the pile in the bin. The decelerator comprises a number of canvas deceleration surfaces 184 each supported within an openended box construction 185 by its own wire frame 188. Together these surfaces present a zig-zag deceleration path leading from the top of the box construction to a central position in bin 180.

In order that fruit leaving the decelerator should roll gently onto the pile of apples already in the bin 180, it is of course desirable that the separation of the decelerator from the top of the pile should be maintained at an acceptably small value and this is achieved by the control system 182 referred to above. In essence this control system comprises a sensor rod 184 resting lightly on top of the apples at the edge of the pile, a hydraulic ram 186 acting on an external flange 188 of the decelerator, and a valve 189 actuated by the sensor as the sensor rod is pushed up to open the valve and allow oil to pas through a hydraulic circuit (not shown) from the tank 190 to the ram 186.When the decelerator has been lifted sufficiently by the ram 186 for the sensor rod to have returned to its initial position relative to the valve 189, this latter will automatically return to its closed position with the decelerator/apple separation still within the range of acceptable values.

Reference numeral 191 indicates a vertical guide for the box structure 185.

Returning again to Figure 1, it is desirable, as previously indicated, to be able to alter the width of the machine so as to be able to control the penetration of the fingers into the opposite sides of the apple trees. Accordingly the machine 10 is made as two sections connected together only by sliding guide beams 192 - 197 which can be clamped in place with an associated clamp not shown in Figure 1 but shown for beams 192 - 194 in Figure 13 where it is identified by reference numeral 198.

It will be seen from these two Figures that each set of guide beams 192 - 194 comprises an I-beam (193) passing between two channel beams (192,194) with the web portion of the I-beam provided with a number of cross bars, such as cross bars 200 in Figure 13. These cross bars provide an axle member for two wheels 201, 202 which run between pairs of horizontal guide plates 203 fixed to the inside of channel guides 192, 194.

The clamp 198 at the top web of channel guide 192 comprises a locking member 205 designed to cooperate with a profiled locking block 208. The inside surface of block 208 is angled to co-operate with a guide wedge 210 driven by an operating handle 212.

A second locking block 214 is fixed to the other side of the I-beam web to operate with a profiled block 216 on the top flange of the second channel guide.

Reference numeral 218 indicates guide surfaces for block 208.

When relative movement between the beams is required, then the clamping assembly 198 will be set as shown in Figure 13. However, if the two guide beams are to be locked together, then the handle 212 is turned to move the guide wedge 210 downwards thereby to force the guided locking block 208 sideways. This in turn will also force the I-beam 193 sideways until the locking block and the fixed block are wedged firmly aganst the tops of the channel guides.

Figure 14 shows a modified design of clamping system in which brackets 300, 302 carried on the channel beams 192,194 provide bearing surfaces for the spindle 304 of an operating handle 306.

The spindle 304 supports two locking blocks 308, 310 of which block 308 is free to slide along the spindle. Block 310 is in screw-threaded engagement with the spindle however so that rotation of the handle 306 in a first direction will result in the blocks moving towards one another (to clamp on to the top flange of the I-beam 193) whereas rotation of the handle in the opposite sense will result in the blocks moving away from one another (to unclamp them).

Reference numerals 312,314 indicate pins secured to the blocks 308,310 and arranged to slide in appropriate apertures in the brackets 300, 302 to stop the blocks pivoting around the spindle 304 and jamming.

To change the separation of the two sections of machine 10 when the guide beams are unclamped, the ground wheels on one side of the machine can be steered in a different direction from those on the other side of the machine. In fact it is better if each wheel can be steered entirely independently of the others since this in addition allows the back wheels to be set for side slope operation of the machine so as to point slightly up the slope and prevent sideways drifting of the machine.

Figure 15 shows the hydraulic circuit by which this independent steering can be achieved. Thus referring now to Figure 15, the four ground wheels 118, 220 - 222 are associated with respective hydraulic cylinders 146, 224 - 226 which can move the wheels about their pivot axes 227. A pump 229 for the steering circuit circulates oil through flow dividers 231, 232 to two open-centre, non-reactive hydrostatic steering units 233, 234 and two directional control valves 235, 236 in a vlave control unit 237. Four diverter valves 238 - 241 are also included in the circuit which is completed by the steering cylinders 146,224-226. Reference numeral 251 indicates a pressure release valve in the return line from pump 229 to its oil reservoir (253).

In normal operation the steering units 233,234 operate respectively the front pair of cylinders 226, 146 connected in series and the rear pair 224, 225 also in series. For independent operation of each wheel the four diverter valves are thrown over so that unit 233 controls only cylinder 226, unit 234 only cylinder 225, while valve 235 now controls cylinder 146 and valve 236 controls cylinder 224.

Thus, if it is desired to increase the width of the machine all four wheels may be set to point outboard and the machine driven forward. Conversely, to reduce the width the wheels may all be set inboard. When the desired width is achieved the wheels may be realigned parallel to each other and the diverter valves thrown back to their normal position.

The steering linkage geometry may be so arranged that the inside wheels turn the sharper radius required on a corner than the outside ones so that side slip is minimized.

In operation of the apple harvesting machine above described, the width of the machine is first adjusted if necessary as already discussed to suit the particular trees under consideration.

The four wheels are then steered to align the machine with the row of trees and if these are on a side slope, then the rear wheels may be set to point slightly up the slope to prevent side drift of the machine. Thereafter any steering to be done as the machine progresses along the row e.g. to deal with local irregularities in the ground surface, is normally done by the front wheels.

During picking, the driver is seated at 260 (in Figure 1) with the appropriate controls (not shown) in front of him and the machine is driven straddlefashion along the row typically at between 1/4 and 11/4 mph with the hydraulic control circuit shown in Figure 10 ensuring that the machine and finger speeds are so related that the relative motion of the fingers through the branches of the trees is substantially vertical. Fruit dislodged by the combing action of the fingers, rolls or slides sidewards across the inclined support surface provided by the fingers on to the conveyors 14 which carry the fruit upwardly for eventual discharge into the collection bins via unloading devices already described.

Conveniently, these bins could be handled by conventional automatic bin-handling equipment dealing say with three bins for each side of the machine.

Figure 16 shows an alternative unloading system comprising a sorting conveyor 262, an intermediate conveyor 264 feeding apples from the main conveyor 14to the sorting conveyor, and a loading conveyor 266 transferring apples from the discharge end of conveyor 262 to a bulk bin 268. The bulk bin is supported on a rotating table 270 mounted on a trailer 272 which includes a plafform 274 on which the sorters can stand as they work. The purpose of having the table 270 rotatable is to allow apples to be evenly distributed as the bin rotates.

Although not shown in Figure 16, the loading conveyor 262 is provided with a control system (e.g. similar or identical to system 182 shown in Figure 12) whose purpose is automatically to raise the loading conveyor as the bin fills to ensure that apples are always discharged directly on to the topmost apples of the pile already in the bin.

In another variation, the bin-handling equipment (serving the same function as items 266-270 of Figure 16) is used to accept apples direct from the conveyor 14. This variation is shown in Figure 17 from which it will be seen that the bin-handling equipment 400 comprises a fork-lift device 402 fed by a spreader 404 from the intermediate conveyor 264 retained from the Figure 16 arrangement.

In more detail, the fork lift device 402 comprises the usual tines 406 powered by a lifting cylinder 408 in conventional fashion. The device 402 differs from conventional fork-lift devices, however, insofar as the fork-lift mast 410 is able to swivel about a vertical axis so as to bring the tines 406 and any bin that they might be supporting either beneath or away from the discharge area of spreader 404. This swivelling motion is achieved by the pivotal connections 412, 413 to a part 415 welded to upright 121 and an extension 416 of the conveyor frame. In addition, extension 416 also supports a support framework 418forthe intermediate conveyor 264.

As will be seen from the drawing, the spreader 404 comprises a plurality of sheet-like flexible fruitreceiving members 420 arranged to rotate about a vertical axis.

In operation, device 402 is used to position an empty bin under the discharge region of spreader 404. Belt 264 and spreader 404 are then put in motion so that fruit from belt 264 is discharged on to spreader 404 which then carries it round until it reaches a point where the level of fruit already in the bin (not shown) is low enough to allow more fruit to roll "through" the spreader. When fruit is carried right around the bin without this point being reached, it will operate a microswitch (not shown) which will open a solenoid valve to lower the bin so that the next layer of fruit will be deposited.

When the bin is filled, device 402 can be used to remove it from beneath the spreader and to replace it by another (empty) bin.

Turning nowto Figures 18 and 19, these show an assembly 500 for catching any fruit which falls past the picking members instead of rolling or sliding along their lengths to the conveyor belt 14 as intended.

The assembly 500 comprises a framework 502 rigidly mounted by brackets 504, 505 on the machine frame 507. Aflighted collector conveyor 509 is mounted in the underside of the framework to collect and transport fruit to a discharge station at the rear end of the conveyor 509.

To break the fall of the fruit and thereby significantly reduce the likelihood of damage, a number of fruit-catching decellerator members 511-514 is provided.

The members 511-514 are each of a flexible sheet-like construction as will be clear from the drawings. The distal edges of these sheets are supported by elastic strings passing through edge seams of the sheets and connected to appropriate parts of the machine frame 507. Alternatively a semi-rigid self-supporting material may be used for members 511-514 or they could be supported by elastic strings connected between frame 507 and the free corners of the members.

At its base edge, member 511 is supported from the machine frame 507 whilst members 512,513 extend from spring wires 515, 516 carried by an overhanging framework 518. This framework comprises first strut members 520 extending upwardly from framework 502 and second strut members 521 secured to the upper ends of members 520. Spring wires 515,516 and framework 518 are padded to lessen the risk of fruit damage.

As will be seen from Figure 19, the base edge of the remaining member 514 is carried by an auxiliary framework 522 (not shown in Figure 18) which is gravity biassed to urge member 514 into engagement with the trunk or stem of the fruit bearing tree 523.

Although only one fruit-catching assembly 500 has been referred to so far, there will of course be a second such assembly (524) on the other side of the tree 523 as Figure 19 makes clear.

Turning lastly to Figure 20, this shows a branch lifting device 600 comprising a framework 602 connected by a pivot to the top of the conveyor frame 606. At this forward end, the framework 602 carries two lifting tines 608. In operation of the device, the branches of the fruit-bearing trees will pass along these tines and up over the framework 602 to a height at which the fruit picking elements 16 can commence to operate.

Although apple-harvesting has been particularly referred to throughout the above description, it will nevertheless be appreciated that a machine of modified form but still according to the present invention could be designed to deal with other fruit.

Alternatively it may well be that the embodiment illustrated would already be suitable for at least one other fruit, i.e. pears.

It will also be appreciated that if the picking elements are to work satisfactorily, the fruit-bearing plants should preferably be such as to allow a reasonable amount of element penetration into the plant.

Preferably therefore the plants should be centre leader trees (one trunk), of a height and width suitable for the machine and with relatively short branches with the fruit-bearing parts largely consisting of single unformed branches. These branches should preferably be slender so that they can "give" as the picking elements move through them and ideally they should be at right angles to the row.

Trees with these characteristics can be obtained by conventional pruning techniques, or possibly also by chemical growth control or by growing them on appropriate dwarfing rootstocks.

Lastly, although a straddle type of machine has been described in detail above, it will be appreciated that the design could be modified as appropriate to provide a single-sided and/or tractor-mounted machine if so desired.

Claims (56)

1. A mobile harvester machine for harvesting fruit from a row of fruit-bearing plants, the machine comprising a plurality of picking elements adapted during operation of the machine to move upwardly through the plants with at least root portions of the picking elements moving relative to the machine body up a path that is inclined downwardly in the forwards direction of the machine.

2. A machine as claimed in Claim 1 including drive means arranged to move the picking elements up the path with a component of motion parallel to the ground that is substantially equal and opposite to the motion of the machine along the ground so that, in operation of the machine, the picking elements move upwards through the plants at not more than 45" either side of the vertical.

3. A machine as claimed in Claim 2 in which the picking elements move upwards through the plants substantially vertically.

4. A machine as claimed in any preceding claim including control means adapted automatically to vary the speed of the picking elements in response to changes in the ground speed of the machine whereby the desired motion of the picking elements through the fruit-bearing plants is maintained within acceptable limits.

5. A machine as claimed in Claim 4 in which the control means comprises a fluid metering unit responsive to changes in the ground speed of the machine to vary the fluid flow to one or more fluid motors used to drive the picking elements relative to the machine body.

6. A machine as claimed in claim 5 in which the control means includes a transducer driven by one of a number of ground wheels supporting the machine or by an additional ground wheel.

7. A machine as claimed in Claim 5 in which the fluid flow to the or each fluid motor is controlled by a valve driven by a mechanically, electronically, or, optically-operated plant sensor.

8. A machine as claimed in Claim 5 in which the fluid flow to the or each fluid motor is controlled by a valve that is manually controlled with the operator estimating the changes in element speed required to compensate for changes in the ground speed of the machine.

9. A machine as claimed in any of Claims 1 to 3 including means to sense the motion of the picking elements relative to the ground and to control the ground speed of the machine accordingly.

10. A machine as claimed in any preceding claim designed to straddle the rows of fruit-bearing plants with the picking elements arranged to be some on one side and some on the other side of the row during operation of the machine.

11. A machine as claimed in Claim 10 in which the machine includes adjustment means for varying the separation of the picking elements on one side of the row from the picking elements on the other side of the row.

12. A machine as claimed in any preceding claim in which the machine body is formed as two interconnected sections, one associated with the picking elements on one side of the row and the other with the picking elements on the other side of the row, the width of the machine being adjustable by varying the positions of the two sections relative to one another.

13. A machine as claimed in Claim 12 in which the ground wheels on one side of the machine can be steered independently of the ground wheels on the other side of the machine and the width of the machine can be varied at will by steering the ground wheels on the one side of the machine in a different direction to the ground wheels on the other side of the machine.

14. A machine as claimed in any preceding claim in which the picking elements are resilient to reduce or prevent damage to fruit and plants during picking.

15. A machine as claimed in any preceding claim in which each picking element is an elongate element with the length of the element chosen to suit the size of plant involved and the stiffness chosen to cope with different varieties of plant.

16. A machine as claimed in Claim 15 and designed for apple harvesting, each picking element comprising a rigid or semi-rigid core member, surrounded by a layer of highly-resilient material provided with a protective outer layer.

17. A machine as claimed in Claim 16 in which the core member is a glass-reinforced polymer rod.

18. A machine as claimed in Claim 16 or Claim 17 in which the resilient material is a polyester foam.

19. A machine as claimed in any of Claims 16 to 18 in which the protective outer layer is an elastomer skin.

20. A machine as claimed in any preceding claim in which the stiffness of the elements varies along their lengths.

21. A machine as claimed in Claim 20 in which the core member tapers towards the distal end of the element.

22. A machine as claimed in any preceding claim in which the picking elements are positioned sufficiently close together so as themselves to present a support surface for the picked fruit.

23. A machine as claimed in Claim 22 in which the picking elements present an inclined support surface along which the picked fruit can roll or slide towards the root portions of the elements and on to or into an appropriate collection and/or transport device provided at or adjacent said root portions.

24. A machine as claimed in Claim 23 in which the collection and/or transport device is a conveyor belt.

25. A machine as claimed in any preceding claim in which the elongate elements take the form of rod-like elements.

26. A machine as claimed in Claim 25 in which the elements curve upwardly at their distal ends to encourage picked fruit to roll or slide on to the support surface provided by the elements.

27. A machine as claimed in Claim 26 in which the elements curve upwardly at their distal ends in a 45" arc.

28. A machine as claimed in Claim 26 or Claim 27 in which the upturned end portion of the elements terminates in an end part which is relatively stiff (as hereinbefore defined) and whose function is to reduce or resist the local downwards depression of the element that might otherwise occur at the distal end of the element during picking.

29. A machine as claimed in any preceding claim in which the picking elements are arranged to have the root portions of at least some of the picking elements deliberately misaligned to discourage fruit from rolling or sliding over successive elements to the front of the machine, the elements thereby loosely defining channels leading from the distal ends of the elements towards their root portions.

30. A machine as claimed in any preceding claim in which the root portions of the elements are carried by carriages mounted to run on appropriate guide rails on the machine body.

31. A machine as claimed in Claim 30 in which two or more banks of elements are mounted on each carriage.

32. A machine as claimed in Claim 30 or Claim 31 in which the carriages are interconnected to form a continuous chain of carriages and in one such case this carriage chain is arranged to be driven by a sprocket wheel.

33. A machine as claimed in Claim 32 in which the sprocket wheel engages with abutments presented by the various carriages.

34. A machine as claimed in any of Claims 1 to 15 in which the picking elements each take the form of one or more rotating brushes.

35. A machine as claimed in any preceding claim in which the inclined path for the picking elements takes the form of two or more inclined pathways arranged so that together the various pathways span the fruit-bearing sections of the plants.

36. A machine as claimed in any of Claims 1 to 34 in which the inclined path is provided by a single pathway inclined at less than 70" to the ground surface.

37. A machine as claimed in Claim 36 in which the pathway is inclined at less than 45" to the ground surface.

38. A machine as claimed in Claim 37 in which the pathway is inclined at between 25" and 35 to the ground surface.

39. A machine as claimed in Claim 38 in which the pathway is inclined at substantially 30 to the ground surface.

40. A machine as claimed in Claim 35 in which there are two said pathways and these are inclined at between 10 and 20 to the ground surface.

41. A machine as claimed in any preceding claim including means to vibrate the plants local to the picking elements either directly by the elements or by a conventional vibrator.

42. A machine as claimed in any preceding claim including avibration-device at the rear of the machine to shake off fruit not previously removed by the picking elements.

43. A machine as claimed in Claim 42 in which the vibration device is a substantially horizontal finger wheel

44. A machine as claimed in any preceding claim including one or more resilient fruit-catching members provided to catch fruit knocked off but not caught by the picking elements and, if present, by the vibration device at the rear of the machine.

45. A machine as claimed in Claim 44 in which the or each fruit-catching member is provided at the bottom of the machine.

46. A machine as claimed in Claim 44 or Claim 45 in which the or each fruit-catching member compris es a flexible sheet suspended beneath the picking elements.

47. A machine as claimed in Claim 46 in which the sheet or sheets slope down towards a conveyor surface so as to deliver to said conveyor surface fruit caught by the fruit-catching members.

48. A machine as claimed in any of Claims 44 to 47 in which the or at least one said fruit-catching member is biased towards a position in which, in operation of the machine, it will engage the trunk or stem of the fruit bearing plant on which the picking elements are currently operating.

49. A machine as claimed in any preceding claim, provided, at its front end, with one or more branch-lifting devices adapted, in operation of the machine, to lift the branches of the fruit bearing plants on which the machine is to operate.

50. A machine as claimed in Claim 49 in which the or each branch-lifting device comprises a ground skid with two upwardly inclined members.

51. A machine as claimed in any preceding claim including a bin handling equipment comprising bin-lifting means arranged to swivel about an axis lying perpendicularly to the ground surface and a rotary fruit spreader positioned so as in operation of the machine to transfer fruit from the upper end region of said inclined path to a bin removable by said bin-lifting means.

52. A machine as claimed in Claim 51 in which the bin-lifting means comprises a fork lift device.

53. A machine as claimed in Claim 51 or Claim 52 in which the fruit spreader comprises a plurality of flexible fruit-receiving members partly overlapping one another in a diaphragm-like construction the rotation axis of the spreader coinciding with an axis of symmetry of said construction lying substantially perpendicular to the plane or planes of the fruitrceiving surfaces.

54. A machine as claimed in Claim 1 and substantially as hereinbefore described with reference to, and as illustrated in the accompanying drawings.

55. A method of continuously harvesting fruit from successive plants in a row of fruit-bearing plants, the method comprising moving picking ele ments up a path that is inclined downwardly in the overall direction of harvesting with the component of motion of the picking elements parallel to the ground surface opposite to the overall direction of harvesting and of a magnitude such that the picking elements move substantially vertically upwards through the plants.

56. A method as claimed in Claim 55 utilising a mobile harvester machine as claimed in any of Claims 1 to 54.