WO2012071606A1

WO2012071606A1 - Sugar cane harvester

Info

Publication number: WO2012071606A1
Application number: PCT/AU2011/001544
Authority: WO
Inventors: Wayne John Brown
Original assignee: Waybro Pty Ltd
Priority date: 2010-11-29
Filing date: 2011-11-28
Publication date: 2012-06-07

Abstract

A sugar cane harvester for harvesting cane stalks, planted in closely-spaced rows, has a harvesting apparatus mounted on a prime-mover. The harvesting apparatus has a pair of stripping heads, separated by a stripping passage, which advance along the row of cane stalks to be harvested. Each stripping head has front and rear continuous carriers, provided with spaced blades or spikes, where the blades or spikes travel in an upward, rearwardly-inclined path, within the stripping passage, to engage and strip leaf - and other matter from the cane stalks before a topping cutter cuts the cane stalks to length and a base cutter then cuts the cane stalks from their rootstock. Brushes can be provided on the continuous carriers to assist the stripping of the leaf matter from the cane stalks; and fans can also be provided rearwardly of the harvesting apparatus to further assist the stripping of the leaf matter. A pair of vertically-spaced stalk conveyors engage, and transfer the harvested cane stalks, to bins or hoppers on the prime-mover for collection and selective-discharge of the harvested cane stalks. The harvester can be provided to harvest other single- or twin-rows of the cane stalks.

Description

TITLE: SUGAR CANE HARVESTER

BACKGROUND OF THE INVENTION

1. Field of the Invention:

This invention relates to a sugar cane harvester. The invention particularly relates, but is not limited to, a stick-type sugar cane harvester, where the cane stalks are harvested whole, or substantially whole, and where any leaf- or other (trash) material is stripped from the stalks.

2. Prior Art:

Originally, sugar cane was cut by hand, using sharp cane-knives. Cane-cutting was hard, back-breaking, work; and originally was often carried out by slaves or poor, indentured, workers. In the 1950's, harvesting started to become mechanised, and early stick-type cane harvesters were developed e.g. by Massey Harris, then Massey Ferguson, in Australia.

In the 1970's, billet cane harvesters were developed and became the preferred sugar cane harvesters in many large sugar-producing countries, including Australia and Brazil.

All harvesting, whether by hand or machine, was carried out after the sugar cane had been burnt. The fires not only removed most of the leaf - and trash material, but also killed the snakes, other reptiles and rodents living amongst the sugar cane. The leaf- and other trash material reduced the efficiency of the harvesters, while the snakes and other animals made working conditions unsafe.

In the 1980's - 1990's, sugar harvesters which could harvest ^agreen" cane i.e. unburnt cane, where the leaf- and trash material was separated from the cane stalks, after the stalks had been cut into the billets, in trash extractors. The trash extractors have large fans, which generate strong airflows to strip the leaf material from the billets and deposit the leaf material onto harvested area to provide mulch for the next crop rotation. Many of the billet sugar cane harvesters are single-row, and are designed to harvest the cane at e.g. 1.5-1.8 metre row spacing's. The harvesters are typically wheel-mounted; but crawler-type tracks are preferred in soils which cannot withstand high footprint loadings or are liable to become boggy. Examples of known sugar canes harvesters are disclosed in, by way of example only, US 2004/0224735 A1 (Hinds); US 5,129,219 (Baker); International Publication WO 2006/059689 A1 (Schalker Eisenhuette Maschinenfabrik GMBH); US 5,303 ,533 (Caillouet); and US 5,463,856 (Beckwith). In particular, WO 2009/059689 discloses a method for harvesting sugar cane in to cleaned stalks, and a harvesting machine therefore; where inclined stripping rollers mechanically strip the leaves from the sugar cane stalks down the stalks before the stalks are topped and cut from the rootstock. To enable the leaves to be stripped, the method requires the tops of the cane stalks to be held as the leaves are pulled down the stalks; and the top of the stalks must be held by a further mechanism while the stalks are topped.

SUMMARY OF THE PRESENT INVENTION It is an object of the present invention to provide an apparatus for stripping the leaf and/or other trash material (hereinafter throughout the description and claims referred to as "leaf matter") upwardly from sugar cane stalks as the apparatus advances along a row of sugar cane. It is a preferred object to provide an apparatus which can lift and/or straighten fallen sugar cane, with minimal, if any, damage to the cane stalks (or loss of sugar content).

It is a further preferred object to provide an apparatus which tops the cane stalks before the cane stalks are stripped of the leaf matter. It is a still further preferred object to provide a harvesting apparatus for sugar cane, incorporating the stripping apparatus, where the cane stalks are cut from their rootstock after the leaf matter has been stripped there-from. It is a still further preferred object to provide a sugar cane harvester, having at least one harvesting apparatus, able to harvest one or more rows of cane stalks spaced less than 1 metres, preferably as little as 0.9 metres, apart.

Other preferred objects of the present invention will become apparent from the following description.

In one aspect, the present invention resides in a stripping apparatus for sugar cane, including:

a pair of stripping heads, separated by a stripping passage, to be advanced along a row of sugar cane stalks to be stripped;

each of the stripping heads having respective forward and rearward continuous carriers, each provided with a plurality of spaced stripping members arranged to extend into the stripping passage; and

drive means for the continuous carriers; so arranged that:

the forward and rearward continuous carriers move the stripping members into engagement with cane stalks at, or adjacent, a lower end of the stripping passage, and then along an upward- and rearward path through the stripping passage, to strip leaf matter from the cane stalks. Preferably, the continuous carriers are chains, or cables, passing around rotary supports at upper and lower ends of the stripping heads.

Preferably, the stripping members are spikes, blades or brushes which extend laterally from the continuous carriers and across a centre-line of the stripping passage; and, preferably, the spikes, blades or brushes on the forward and rear carriers of one of the stripping heads are interleaved with the respective spikes, blades or brushes of the forward and rear carriers of the other stripping head.

Preferably, at least the rotary supports at the lower ends of the stripping heads direct the spikes or blades along paths transverse to the stripping passage, so that the spikes or blades are substantially vertical, in side view, as the spikes or blades engage the cane stalks.

Preferably, the paths of the spikes or blades are substantially perpendicular to the row of cane stalks in top plan view.

Preferably, the upward-and rearward paths of the spikes or blades are inclined in the range 1 ° to 40° to the vertical; more preferably 10° to 30°; most preferably, 20°; in side view.

Preferably, the horizontal vector of the travel of the spikes, blades or brushes within the stripping passage is substantially equal, but oppositely directed to, the velocity of the advance of the stripping apparatus along the row of sugar cane. Preferably, on each stripping head, a spike, blade or brush on the forward carrier engages one side of a cane stalk entering the stripping passage before a spike, blade or brush on the rearward carrier engages an opposite side of the cane stalk; the spikes, blades or brushes then moving upwardly along the cane stalk to strip the leaf matter there-from.

Preferably, the stripping members include a first set of stripping brushes mounted on the forward carrier of each stripping head, adjacent to, or on, a respective spike or blade, to assist in stripping the leaf matter from the cane stalks. A second set of stripping brushes may be provided on respective carrier bars, interconnecting the forward and rearward carriers, and preferably arranged forwardly of the spikes or blades of the rearward carrier of each stripping head.

In an alternative embodiment, the first set of stripping brushes are mounted on respective spikes which are rotatably journalled on the forward carrier and are rotatably driven as the spikes enter and move upwardly within the stripping passage. Each spike may be provided with a pinion-gear which engages a complementary rack on the front carrier, so arranged to rotatably drive the spike so that the first stripping brush moves either counter-current, or concurrent, with the movement of the spike upwardly along the cane stalk. In a second aspect, the present invention resides in a harvesting apparatus for ' sugar cane, including:

a stripping apparatus as hereinbefore described; and

a base cutter rearwardly of the lower end of the stripping passage to cut the cane stalks from rootstock of the cane stalks when at least substantially all of the leaf matter has been stripped from the cane stalks.

Preferably, the base cutter is arranged to cut the cane stalks after the cane stalks have been released by the stripping members of the stripping apparatus.

Preferably, a cane-lifting apparatus has a pair counter-rotating spirals extending forward ly of the stripping apparatus to assist in guiding the cane stalks in the row being harvested towards the stripping passage. Preferably, the spirals are convergent in top plan view, and rearwardly- and upwardly inclined in side view.

Preferably, a topper apparatus is provided forwardly of, and adjacent to, an upper end of the stripping passage, to cut tops from the cane stalks before the cane stalks are released by the stripping members. Preferably, a first cane stalk cleaning apparatus is provided intermediately the lower end of the stripping passage and the base cutter. Preferably, a second cane stalk cleaning apparatus is provided rearwardly of the base cutter.

Preferably, the respective stalk cleaning apparatus comprise overlapping cleaning wheels rotating about respective substantially-horizontal axes, substantially parallel with the centre-line of the stripping passage in top plan view, the cleaning wheels having paddles or other members to create a non-linear path for the lower ends of the cane stalks to strike the cane stalks, or to generate an airflow around the cane stalks, to dislodge the leaf matter (and any entrained soil, rocks or other rubbish) there-from.

In a third aspect, the present invention resides in a sugar cane harvester including:

a prime-mover mounted on wheels, crawler-tracks or the like, to advance along one or more rows of sugar cane; at least one harvesting apparatus, as hereinbefore described, mounted on the prime-mover to harvest the, or a respective, row of the sugar cane;

at least one receptacle for the cane stalks harvested by the, or each, harvesting head;

at least one conveying apparatus to transfer the harvested cane stalks from the, or each, harvesting head to the, or each, receptacle; and

at least one power source on the prime-mover for the harvester.

Preferably, the prime-mover is mounted on a pair of crawler-tracks. However, the prime-mover may be mounted on at least three, more preferably four wheels, where a least one pair of the wheels are steered, or the wheels are arranged for skid- steer operation. Preferably, the crawler-tracks or wheels have a low-pressure footprint. Preferably, the power source is an internal combustion engine, e.g. a diesel engine, which is operably connected to a transmission (e.g. hydrostatic drive) for the crawler-tracks or wheels of the prime-mover; and is operably connected to one or more hydraulic pumps to drive associated motors and/or hydraulic cylinders, or rams, for the harvesting apparatus and conveying apparatus

Preferably, the at least one receptacle includes a pair of bins or hoppers selectively movable to enable discharge of the harvested cane stalks from one bin or hopper while the other bin or hopper receives the harvested cane stalks. Preferably, the receptacle(s) are mounted on the prime-mover (e.g. for side-tipping by hydraulic ram(s)), but may be provided on a trailer towed thereby.

Preferably, the conveying apparatus includes a pair of vertically- spaced stalk conveyors, which are preferably divergent in side view; and where the upper of the conveyors may be raised or lowered to suit different cane stalk lengths. Preferably, the upper of the conveyors has at least one combing chains, where the harvested cane stalks are engaged between rearwardly-moving runs of the combing chain(s). Preferably, the lower of the conveyors has pairs of rotating sprockets or plates, or rubber pads on chains, provided at spaced intervals, to engage the harvested cane stalks passing there-between. In respective fourth, fifth and sixth aspects, the present invention resides in methods for stripping, harvesting and harvesting sugar cane stalks using the apparatus of the first, second and third aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

To enable the invention to be fully understood, preferred embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a schematic isometric view of a track-mounted sugar cane harvester in accordance with a first embodiment of the present invention;

FIG. 2 is a rear isometric view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a side elevational view thereof, parts being omitted for clarity;

FIG. 7 is a similar view to FIG. 6, with the prime-mover being omitted, but illustrating alternative wheel-mountings for the prime-mover;

FIG. 8 is a sectional side-view taken along the centre-line of the harvester; FIG. 9 is a front elevational view of the harvesting head, parts being omitted for clarity;

FIG. 10 is a front isometric view of the harvesting apparatus, where the brushes have been omitted for clarity;

FIG. 11 is a top isometric view thereof;

FIG. 12 is a side isometric view thereof;

FIG. 13 is a schematic front view of the paths of the spikes or fingers;

FIG. 14 is a schematic side view thereof;

FIG. 15 is a view similar to FIG.10, where the brushes have been included;

FIG. 16 is a front isometric view of a portion of the harvesting apparatus of FIG 15, on an enlarged-scale;

FIG. 17 is schematic side view showing the operation of the harvesting apparatus;

FIG. 18 is a similar view, on a reduced scale, of the operation of the sugar cane harvester; FIG. 19 is a schematic front elevational view of the harvesting apparatus of a twin-row sugar cane harvester in accordance with a second embodiment of the present invention;

FIG. 20 is a schematic top plan view thereof; and

FIG. 21 is a schematic view of the mounting and rotational drive for spikes fitted with the first stripping brushes.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As illustrated in FIGS.1 , 2, 17 and 18 of the accompanying drawings, the sugar cane stalks S are (schematically) shown standing erect "like soldiers-on-parade". The skilled addressee will appreciate that most of the cane stalks S will be bent, and may even be horizontal, in directions along, or at angles (e.g. extending laterally), to the respective rows R of the sugar cane stalks S, and that the sugar cane harvester 10 of the present invention will be able to lift, straighten, strip and cut such cane stalks S into cleaned (harvested) cane stalks S

As illustrated, e.g., in FIGS. 1 and 2, the sugar cane stalks S are grown in rows R spaced, e.g., 1.0 metres apart, the sugar cane stalks S being grown in raised stools ST separated by respective "valleys" G at the ground level.

Leaf- and other trash material L surround at least the upper portions of the respective sugar cane stalks S. Referring to FIGS. 1 to 8, the single-row sugar cane harvester 10, in accordance with the first preferred embodiment of the present invention, has a chassis 11 supported by a pair of crawler-tracks 12, spaced to travel along the "valleys" G, each crawler-track 12 being selectively driven by a hydraulic motor 13 connected to the rear track sprocket 14 of each crawler-track 12.

A diesel engine 15 is mounted in an engine compartment 16 at the rear of the chassis 11 and drives a hydraulic pump 17 which is operably connected, via suitable controls (not shown) within an operator's compartment 18, to the hydraulic motors 13, to provide a hydrostatic drive transmission system for the sugar cane harvester 10. The operator's compartment 18 is mounted above one side of the chassis 11 , on a post 19, and is elevated relative to the chassis 11 to enable the operator O to have a clear view of the operation of the harvesting apparatus 20 (to be hereinafter described in more detail) as the sugar cane harvester 10 advances along a row R of the sugar cane stalks S being harvested.

By arranging the diesel engine 15 transversely at the rear of the chassis 11 , and relatively low to the ground, the diesel engine is contained within the overall 1.4 metre width of the sugar cane harvester 10, and provides a stable counter-balance to the weight of the harvesting apparatus 20 extending forwardly of the harvester chassis 11.

As illustrated in dashed lines in FIG. 7, the crawler-tracks 12 may be substituted by (i) a pair of driving wheels DW on each side of the chassis 1 , arranged to operate in a skid-steer like operation; or by (ii) one or two drive wheels DW on each side of the chassis, where the sugar cane harvester 10 is steered by steerable wheels SW connected a suitable steering mechanism (not shown) controlled from the operator's compartment 18. To minimise damage to the "valleys" G, it is preferable that the crawler-tracks

12, or wheels DW, SW, have a "low-pressure" footprint.

The single-row harvesting apparatus 20 has a stripping apparatus 30 incorporating a pair of stripping heads 31 , 32 (to be hereinafter described in more detail), separated by a stripping passage 33 which is substantially aligned with the row R of the sugar cane stalks S to be harvested. NB: As the stripping heads 31 , 32 are "mirror-images", all future description will refer to stripping head 31 only; where the skilled addressee will appreciate that, unless otherwise described, the respective features of the stripping heads 31 , 32 are identical. Cane-lifting apparatus 40 extends forwardly of the stripping apparatus 30, where respective crop-lifting spirals 41 are arranged to lift and direct the cane stalks S in the row R being harvested towards the stripping apparatus 30 as the sugar cane harvester 10 advances along the row R. Each cane-lifting spiral 41 has a (preferably downwardly-convergent) frusto- conical body 42, provided with an external helical-screw like formation 43; the spiral body 42 being mounted on a shaft (not shown) rotatably journalled in a bearing assembly 44 adjacent the forward distal end of a substantially-horizontal foot plate 45 extending forwardly from the lower end of a cane-lifter support frame 46 mounted on a respective stripping head 31 , where the upper end of the shaft is connected to a respective hydraulic drive motor 47, in turn connected to a hydraulic pump and controlled from the operator's compartment 18.

Preferably, the cane-lifting support frame 46 is adjustably mounted on the stripping head 31 to enable the height of the foot plate 45 (and thereby the cane- lifting spiral 41 above the valley G to be selectively adjusted.

A cane-topping apparatus 50 is mounted forwardly of the stripping apparatus 30, adjacent the upper end of the stripping passage 32, the cane-topping apparatus 50 having a cane de-topper 51 with a plurality of (substantially radially extending) de- topping blades 52 extending from a topper drum 53 rotatably journalled in top and bottom plates 54, 55 of a cane de-topper support frame 56 adjustably mounted on the stripping heads 31 , 32. The de-topping drum 53 may be driven by a hydraulic motor or, alternatively, by a mechanical drive 57 where an input shaft 58 has a driving sprocket 59 preferably engaged with the continuous carrier (to be hereinafter described) of the stripping head 31 , the input shaft 58 driving a gearbox 60, the output of which is operably connected to the topper drum 53.

In an alternative embodiment, the bottom plate 55 is provided with the, or additional, blades 52 and is rotatably driven.

By selectively adjusting the location of the cane-topping apparatus 50 relative to the stripping heads 31 , 32, the bulk of the leaf matter L at the top of the cane stalks S may be "de-topped" before the cane stalks S are engaged by the spikes or blades (to be hereinafter described) of the stripping heads 31 , 35; and to also selectively set the length of the cane stalks S when harvested. As the de-topped leaf matter L is selectively thrown to the side of the sugar cane harvester 10 where the rows R of cane stalks S have been harvested, the leaf matter L may be left undisturbed to provide mulch for the next planting of the sugar cane. As hereinbefore described, the stripping apparatus 30 has a pair of identical stripping heads 31, 32 which are "mirror-images" and which are arranged so that the stripping passage 33 therebetween is rearwardly-convergent in top plan view, ie., the stripping heads 31 , 32 assist in "funnelling" the cane stalks S towards the stripping passage 33 to enable the leaf matter L to be stripped from the cane stalks S in the manner to be hereinafter described in more detail.

As illustrated in, eg., FIGS. 1 , 7 and 8, the stripping heads 31 , 32 are rearwardly-inclined to the vertical, in side view, from their lower ends to their upper ends at an angle of 15°-20°. The construction of the stripping heads 31, 32 will now be described in more detail with reference to FIGS. 9 to 16.

The stripping head 31 has front and rear columns 34, 35 interconnected by top and bottom cross-beams 36, 37 (and optional internal braces) to form a stripping head frame 38 which is substantially rectangular in side elevational view. Respective front and rear bearing support plates 70, 71 are adjustably mounted on the front and rear columns 34, 35 and each support plate 70, 71 , at its upper distal end, supports a bearing assembly 72 on which a top carrier shaft 73 is rotatably-journalled, the top carrier shaft 73 being connected to a hydraulic motor 74, in turn connected to a hydraulic pump via suitable valves controlled from the operator's compartment 18. Front and rear top carrier sprockets 75, 76 are keyed to the top carrier shaft 73 to rotate therewith; or may be rotatably journalled on the top carrier shaft 73 by bearings. At the lower end of the stripping head frame 38, front and rear lower support plates 77, 78 extend below the columns and are provided with similar bearing assemblies 79 to rotatably-journal the bottom carrier shaft 80 to which is keyed front and rear lower carrier sprockets 81 , 82 having teeth complementary to the teeth on the upper carrier sprockets 75, 76. The lower carrier sprockets 81 , 82 have the form of a "shallow dish" with the teeth around the circumference, so arranged that, as will be described hereinafter with reference to FIGS. 13 and 14, the spikes or blades follow "substantially-frusto-conicar paths, where the paths are substantially- perpendicular to the row of cane stalks in top plan view, and the spikes or blades will be substantially vertical as they enter the stripping passage 33 and engage the lower portions of the cane stalks S. Front and rear carrier chains 83, 84 pass around respective upper and lower carrier sprockets 75, 76, 81 , 82, the upper carrier sprockets 75, 76 being drivingly engaged with their carrier chains 83, 84, while the lower carrier sprockets 81 , 82 act as tail sprockets. A plurality of "idler" sprockets 85 may be provided extending to either or both sides of the front and rear columns 34, 35 to direct and control the respective upwardly-moving and downwardly-moving runs 86, 87 and 88, 89 of the carrier chains 83, 84.

The hydraulic motor 74 drives the upper carrier sprockets 75, 76 so that the upwardly-moving runs 86, 87 of the carrier chains 83, 84 within the stripping passage 33 follows an upward (and rearwardly inclined) path at an angle of 15°-20° to the vertical.

NB: The skilled addressee will appreciate that the carrier chains 83, 84 and upper and lower carrier sprockets 75, 76, 81 , 82 may be substituted by cables and pulleys or sheaves.

As illustrated most clearly in FIG. 16, the front and rear carrier chains 83, 84 are interconnected by spaced carrier bars 90 which are bolted (or otherwise fixed) to respective adjacent links of the carrier chains 83, 84.

A blade support bracket 91 extends from the junction of each carrier bar 90 with the front carrier chain 83 and detachably mounts a blade 92 via studs or bolts 93.

Each blade 92 has a base portion 94 mountable on the blade support bracket 91 and an elongate distal portion 95, with parallel stripping edges 96, 97 interconnected by an end face 98, the distal portion 95 and the base portion 94 being interconnected by an intermediate portion 100 with convergent edges 101. The respective inner and outer side faces 102, 103 of the blades 92 lie substantially parallel to, but spaced inwardly from, the adjacent run of the front carrier chain 83.

A respective spike 104 is mounted via a spike base plate 105 on the respective carrier bar 90 adjacent to the rear carrier chain 84, and extends from the carrier bar 90 substantially parallel to the respective front blade 92. The spike 104 has a tubular body 106 with a screw-threaded inner end releasably engageable in a socket 107 on the spike base plate 105 and is provided with a locking nut 108. · NB: The skilled addressee will appreciate that the inclination of the stripping head 31, and thereby the carrier chains 83, 84, means that each spike 104 is at a height interposed between an adjacent pair of the blades 92, in side view.

A first stripping brush assembly 110 is mounted on each blade 92 and has four brushes 111 extending from the side faces 102, 103 Of the blades 92 in substantially horizontal V-shaped configurations.

A second stripping brush assembly 112 is mounted on each carrier bar 90, intermediate the blade 92 and spike 104, and has a pair of brushes 113 extending forwardly from the carrier bar 90 in a substantially V-shaped formation in top plan view.

When viewing the carrier bar 90 interconnecting the upward runs 86, 87 of the front and rear carrier chains 83, 84, the blade 92 will be at a greater height than the second stripping brush assembly 112 which, in turn, will be at a greater height than the spike 104 on that carrier bar 90.

The bristles of the brushes 111, 113, may be manufactured from a wide range of materials, including natural fibres or plastics. The materials used in the manufacture of road-cleaning brushes are particularly suitable, as they are stiff and long-wearing.

As illustrated in FIGS. 7 and 8, a first cane stalk cleaning apparatus 120 is located rearwardly of the lower end of the stripping passage 33 and is aligned therewith.

The first cane stalk cleaning apparatus 120 has a plurality of overlapping cleaning wheels 121 rotating about a pair of substantially horizontal axes 122, the axes 22 being substantially parallel with the centre line of the stripping passage 33 in top plan view. The wheels 121 create a non-linear path for the lower ends of the cane stalks S. The cleaning wheels 121 have paddles 123 to strike the lower ends of the cane stalks S to dislodge leaf matter L and any entrained soil, rocks, or other rubbish therefrom.

The cleaning wheels 121 are operably driven by a hydraulic motor 124 connected to a hydraulic pump and controlled from the operator's compartment 18 as hereinbefore described.

A cane stalk base cutter 130 is mounted on the chassis 11 rearwardly of the first cane stalk cleaning apparatus 120 and rotates about an axis 131 aligned with the centre line of the stripping passage 33, but inclined to the vertical in side view - see FIG. 8. The cane stalk base cutter 130 has a disc-like cutting plate 132 provided with a plurality of cutter blades 133 extending substantially radial from the cutting plate 132, the cutting plate 132 being mounted on a shaft 134 driven by a hydraulic motor, 135 also connected to a hydraulic pump and suitable control valves.

The cane stalk base cutter 130 is arranged, as will be hereinafter described, to cut the lower ends of the cane stalks S from their rootstock, just above the tops of the stools ST, while the upper ends of the cane stalks S are still engaged by at least one of the blades 92 or spikes 104 of the stripping heads 31 , 32.

A second cane stalk cleaning apparatus 140 is provided rearwardly of the base cutter 130, aligned with the stripping passage 33. The second stalk cleaning apparatus 140 has cleaning wheels as per the cleaning wheels 121 of the first cane stalk cleaning apparatus 120, or a plurality of fan blades or paddles 141 (driven by a motor 142) operable to generate an air flow and cleaning action around the cane stalks S to ensure all the leaf matter L has been stripped from the cane stalks S.

An upper stalk conveyor 150 has a pair of spaced support beams 151 , 152, upwardly inclined from their forward ends to their rearward ends in side view, and separated by a conveying passage 153 aligned with the stripping passage 33 in top plan view.

Continuous combing chains 154, 155 are supported by head and tail sprockets 156, 157, 158, 159, rotatably journalled at the forward and rearward ends of the respective beams 151 , 152 and the respective forward and rearward runs 160, 161 , 162, 163 of the combing chains 151, 152 are supported by slide sprockets 156, 157 rotatably journalled along the beams 151 , 152. The tail sprockets are operably driven by hydraulic motors 164, 165 at the rearward end of the beams, 151 , 152; each hydraulic motor 164, 165 being connected to a hydraulic pump and controlled from the operator's compartment 18 as hereinbefore described.

The hydraulic motors 164, 165 are counter-rotating so that the rearwardly- directed runs of the combing chains 154, 155 are arranged within the conveying passage 153 to engage intermediate portions of the stalks S before the cane stalks S are cut from their rootstock by the base cutter 130, and are then conveyed rearwardly along an upwardly inclined path.

As illustrated in FIG. 7, the beams of the upper stalk conveyor 150 are adjustably mounted on the chassis 11 via upper stalk conveyor supports 166 to enable the upper stalk conveyor 150 to be vertically adjusted to suit different cane stalk lengths.

If preferred, only a single combing chain 154 may be provided for the upper stalk conveyor 150. The lower cane stalk conveyor 170 has a pair of beams 171 , 172 arranged similarly to the beams 151 , 152 of the upper stalk conveyor 150 and, at the rearward end of each beam 171 , 172, a pair of toothed plates 173, 174 are operably driven by respective hydraulic motors 175, 176 mounted at the rearward ends of the beams 171 , 172.

The beams 171, 172 are mounted on support frames 177 on the chassis 11; and, intermediate their length, are provided with respective rotatably journalled toothed plates 178, 17Θ which are freely rotating and are arranged to be engaged by lower portions of the harvested cane stalks S as the harvested cane stalks are conveyed towards the rear of the sugar cane harvester 10 by the upper stalk conveyor 150.

Alternatively, the lower cane stalk conveyor 170 has a pair of parallel chains, which operate at the same rearward linear velocity; and spaced rubber pads frictionally-grip the cane stalks there-between. A pair of open mouth bins or hoppers 180, 181 , each having a pair of side walls, (optional) front wall, (optional) rear end wall and a floor, are slidably mounted on a support frame 182 at the rear of the chassis 11 and are interconnected to the chassis 11 by respective sliding rams 183, 184 which are connected to a hydraulic pump and which are sequence-controlled from the operator's compartment 18, so that while one of the bins or hoppers 180, 181 is being slid left or right to discharge the harvested cane stalks S therein, the other bin or hopper 181 , 180 is arranged to receive the harvested cane stalks S from the stalk conveyors 150, 170. Usually, the bins or hoppers 180, 181 will be slid sideways to deposit the harvested cane stalks S in piles to either side of the direction of travel of the sugar cane harvester 10. It will be apparent to the skilled addressee that the bins or hoppers 180, 181 may be hinged to deposit the harvested cane stalks S immediately behind the sugar cane harvester 10.

It will also be readily apparent to the skilled addressee that the bins or hoppers 180, 181 may be mounted on a trailer, eg., mounted on a trailer TR provided with wheels W towed behind the chassis 11 of the sugar cane harvester 10. The operation of the sugar cane harvester 10 will now be described. As the sugar cane harvester 10 advances along the row R of the sugar cane to be harvested, the crop lifting spirals 41 assist in lifting the cane stalks S and/or directing them towards the lower end of the stripping passage 33. The respective blades 92 on the downward runs 88 of the front chain carriers

83 of each stripping head 31 , 32 pass around the lower carrier sprocket 81 and adopt a path so that the blades 92 enter into the lower end of the stripping passage 33 with their axes substantially vertical in side view - see FIGS. 13 and 14. As illustrated in, eg., FIG. 9, the blades 92 of the stripping head 31 are interposed between the corresponding blades 92 of the stripping head 32, and both blades slightly overlap the centre line of the stripping passage 33.

One of the blades 92 engages a lower portion of a cane stalk S and moves upwardly and rearwardly along the path defined by its front carrier chain 83, 84. The distal blade portion 95 commences upward stripping of the leaf matter L from the cane stalk S and is assisted thereby by the first stripping brushes 111 provided on the blade 92. The second stripping brushes 113 then engage the lower portion of the cane stalk S before the spike 104 on the same carrier bar 90 engages the (ie., opposite) side of the cane stalk S from the blade 92. As the blade 92, brushes, 111, 113 and spike 104 start to move up the lower portion of the cane stalk S, the upper portion of the cane stalk S engages the cane-topping apparatus 50 and the de- topping blades 52 remove the upper end portion of the cane stalk S (and its associated leaf matter L).

By selection of the relationship between (i) the velocity of advance of the sugar cane harvester 10, (ii) the inclination of the stripping heads 31 and 32, and the (iii) linear speed of the upward run 86, 87 of the carrier chain 83, 84, the blades 92, brushes 111 , 113 and spikes 104 appear to move in a substantially vertical direction in side view up the sugar cane S to strip most, if not all, leaf matter L (and other trash) therefrom.

As the upper end of the (now topped) cane stalk S is released by the blade 92, the lower portion of the cane stalk S passes through the first cleaning apparatus 120 and is "shaken" by the paddles 123 to assist in releasing any attached leaf matter L or other trash therefrom. Then, as the upper portion of the now-topped cane stalk S is released by the spike 104, the cutter blades 133 on the base cutter 130 cut the lower end of the cane stalk S from its rootstock.

The upper and lower stalk conveyors 150, 170 engage intermediate portions of the cane stalks while the sugar cane stalk S is stalled at its upper end by the spike 104 and as it is being cut by the base cutter 130. The now harvested cane stalks S are conveyed rearwardly and upwardly by the rearward runs 162, 163 of the combing chains 151 , 152 of the upper stalk conveyor 150 and are "disturbed" by the toothed plates 173, 174, 178, 179, frictionally-gripped by the rubber pads, on the lower stalk conveyor 170.

, .

Any residual leaf matter L or trash on the cane stalks S is released therefrom as the lower ends of the cane stalks S are engaged by the cleaning wheels, or air flow created by, the second cleaning apparatus 140 rearwardly of the base cutter 130. The now harvested cane stalks S are conveyed to a location above one of the bins or hoppers 180, 181 and deposited therein when released at the rearward end of the upper and/or lower stalk conveyor 150, 170. The skilled addressee will appreciate that the upward movement of the blades

92, brushes 111 , 113 and spikes 104 will tend to straighten the cane stalks S to a substantially vertical position, whilst also stripping all leaf matter L upwardly along the length of the cane stalks S. The skilled addressee will appreciate that the stalk conveyors 150, 170 engage the (now stripped) cane stalks S intermediate their lengths before the cane stalks S are cut from their rootstock by the base cutter 130.

The skilled addressee will also appreciate that there are many variations of the spacing, shape and location of the blades 92, brushes 111 , 113 and spikes 104 on the stripping heads 31 , 32; and that each stripping head 31 , 32 may be provided with blades 92 only or spikes 104 only.

The sugar cane harvester 10 illustrated in FIGS. 1 to 18 is a single-row sugar cane harvester. As illustrated in FIGS. 19 and 20, the harvesting apparatus, including the cane lifting apparatus 40, the topping apparatus 50, the stripping apparatus 30, the cane cleaning apparatus 120, 140, the base cutting apparatus 130 and the upper and lower stalk conveyors 150, 170 may be duplicated to enable a single twin-row harvester 210 to simultaneously harvest two adjacent rows R of sugar cane. The skilled addressee will note that the respective harvesting apparatus 20 are aligned at equal spacings from the centre line of the twin row sugar cane harvester 210 and can deposit the harvested sugar cane stalks S into a single pair of bins 180, 181 , as hereinbefore described. FIG. 21 illustrates an alternative embodiment, where the effectiveness of the first cleaning brushes may be further enhanced.

A first stripping brush assembly 310 is mounted on each spike 304 which is rotatably journalled in a spike base plate 305 mounted on the carrier bar 390 adjacent the front carrier chain 383. The tubular body 306 is extended through the carrier bar 390 to provide a drive shaft 307 which is provided with a pinion gear 308 at its distal end. The pinion gear 308 engages a rack 309, with teeth T complementary to the pinion gear 308. The rack 309 commences adjacent the lower end of the stripping passage 33 and extends upwardly thereby to cause the spike 304 to rotate, thereby rotating the first stripping brush assembly at least within the lower portion, but preferably the full length, of the stripping passage 33. The pinion 308 is disengaged from the rack 309 on the downward travel of the spike 304. Preferably, the pinion 308 engages the rack 309 during the lower portion of the downward travel of the spike 304, so that the pinion 308 can rotate the spike 304, and thereby the first stripping assembly 310 at e.g. 300-500rpm, before the spike 304 commences the transition into the curved path leading to the stripping passage 33.

The rack 309 and pinion 308 may be arranged to rotate the first stripping assembly 310 so that the portion of the brush 311 engaging the cane stalk S is moving downwardly, i.e. counter-current to the upward-travel of the spike 304 within the stripping passage 33; or is moving upwardly, i.e. concurrent to the travel of the spike 304. When the first stripping assembly 310 is rotated so that the brush 311 is moving downwardly when the brush 311 engages the cane stalk S, the rotational speed of the spike 304, and thereby of the brush 311 , will preferably be selected so that the downward velocity of the brush 311 when engaging the cane stalk S is at least several multiples, of the upward velocity of the spike 304 within the stripping passage 33. Typically, the spike 304 will be rotated at no less than 300rpm.

The sugar cane harvesters 10, 210 hereinbefore described and illustrated both (i) enable mechanical harvesting of sugar cane, planted in rows R spaced, e.g., 0.9-1.0 metres apart, which would not otherwise able to be mechanically harvested by existing sugar cane harvesters, and (ii) enable the harvested sugar cane stalks S can be cut to pre-set lengths, while all unwanted leaf matter L or other trash is removed.

'

The compact nature of the sugar cane harvesters enables the harvesters 10, 210 to have a low-pressure "footprint" ensuring minimal damage to the valleys G between the cane stools ST. In addition, the single-row sugar cane harvester 10 may be easily transported between the cane harvesting sites on a small vehicle, e.g., a trailer, without exceeding the usual vehicle width limits (e.g., 2.5 metres). By provision of hydrostatic drive for the crawler-tracks 12 or wheels DW, SW of the prime-mover, and the use of hydraulic pumps and/or rams to operate the various components of the sugar cane harvesters 10, 210, the sugar cane harvesters 10, 210 are very energy-efficient; and the operator O has both a clear working view of all portions of the sugar cane harvesters and precise control of each section thereof.

Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention.

Claims

CLAIMS:

1. A stripping apparatus for sugar cane, including:

drive means for the continuous carriers; so arranged that:

the forward and rearward continuous carriers move the stripping members into engagement with cane stalks at, or adjacent, a lower end of the stripping passage, and then along an upward- and rearward path through the stripping passage, to strip leaf matter from the cane stalks.

2. The stripping apparatus as claimed in claim 1, wherein:

the continuous carriers are chains, or cables, passing around rotary supports at upper and lower ends of the stripping heads; and

the stripping members are spikes or blades which extend substantially laterally from the continuous carriers and across a centre-line of the stripping passage.

3. The stripping apparatus as claimed in claim 2, wherein:

the spikes or blades on the forward and rearward carriers of one of the stripping heads are interleaved with the respective spikes or blades of the forward and rearward carriers of the other stripping head.

4. The stripping apparatus as claimed in claim 2 or claim 3, wherein:

at least the rotary supports at the lower ends of the stripping heads direct the spikes or blades along paths transverse to the stripping passage, so that the spikes or blades are substantially vertical, in side view, as the spikes or blades engage the cane stalks.

5. The stripping apparatus as claimed in any one of claims 2 to 4, wherein:

the upward-and rearward paths of the spikes or blades are inclined in the range to 40° to the vertical; more preferably 10° to 30°; most preferably, 20°; in side view.

6. The stripping apparatus as claimed in claim 5, wherein:

the horizontal vector of the travel of the spikes or blades within the stripping passage is substantially equal, but oppositely directed to, the velocity of the advance of the stripping apparatus along the row of sugar cane being harvested.

7. The stripping apparatus as claimed in any one of claims 1 to 6, wherein:

on each stripping head, a spike or blade on the forward carrier engages one side of a cane stalk entering the stripping passage before a spike or blade on the rearward carrier engages an opposite side of the cane stalk; the spikes or blades then moving upwardly along the cane stalk to strip the leaf matter there-from.

8. The stripping apparatus as claimed in any one of claims 1 to 7, wherein:

the stripping members include a first set of stripping brushes mounted on the forward carrier of each stripping head, adjacent a respective spike or blade, to assist in stripping the leaf matter from the cane stalks.

9. The stripping apparatus as claimed in claim 8, wherein:

the first set of stripping brushes are mounted on respective spikes, the spikes being rotatably journalled on the forward carrier and rotatably driven as the spikes enter and move upwardly within the stripping passage.

10. The stripping apparatus as claimed in claim 9, wherein:

each spike is provided with a pinion-gear which engages a fixed rack on the front carrier, so arranged to rotatably drive the spike so that the first stripping brush moves either counter-current, or concurrent, with the movement of the spike upwardly along the cane stalk.

11. The stripping apparatus as claimed in any one of claims 8 to 10, and further including:

a second set of stripping brushes provided on respective carrier bars, interconnecting the forward and rearward carriers, and arranged forwardly of the spikes or blades of the rearward carrier of each stripping head.

12. A harvesting apparatus for sugar cane, including:

a stripping apparatus as claimed in any one of claims 1 to 11 ; and a base cutter rearwardly of the lower end of the stripping passage to cut the cane stalks from rootstock of the cane stalks when at least substantially all of the leaf matter has been stripped from the cane stalks.

13. The harvesting apparatus as claimed in claim 12, wherein:

the base cutter is arranged to cut the cane stalks after the cane stalks have been released by the stripping members of the stripping apparatus.

14. The harvesting apparatus as claimed in claim 12 or claim 13, and further including:

a cane-lifting apparatus having a pair counter-rotating spirals extending forwardly of the stripping apparatus to assist in guiding the cane stalks in the row being harvested towards the stripping passage.

15. The harvesting apparatus as claimed in claim 14, wherein:

the spirals are convergent in top plan view, and are rearwardly - and upwardly inclined in side view.

16. The harvesting apparatus as claimed in any one of claims 12 to 15, and further including:

a topper apparatus provided forwardly of, and adjacent to, an upper end of the stripping passage, to cut tops from the cane stalks before the cane stalks are released by the stripping members.

17. The harvesting apparatus as claimed in any one of claims 12 to 16, and further including:

a first cane stalk cleaning apparatus is provided intermediately the lower end of the stripping passage and the base cutter.

18. The harvesting apparatus as claimed in claim 17, and further including:

a second cane stalk cleaning apparatus provided rearwardly of the base cutter.

19. The harvesting apparatus as claimed in claim 17 or claim 18, wherein:

the respective stalk cleaning apparatus comprise overlapping cleaning wheels rotating about respective substantially-horizontal axes, substantially parallel with the centre-line of the stripping passage in top plan view, the cleaning wheels having paddles or other members forming a non-linear path for the lower ends of the cane stalks to strike the cane stalks, or to generate an airflow around the cane stalks, to dislodge the leaf matter, and any entrained soil, rocks or other rubbish, there-from.

20. A sugar cane harvester including:

a prime-mover mounted on wheels, crawler-tracks or the like, to advance along one or more rows of sugar cane;

at least one harvesting apparatus, as claimed in any one of claims 12 to 19, mounted on the prime-mover to harvest the, or a respective, row of the sugar cane; at least one receptacle for the cane stalks harvested by the, or each, harvesting head;

at least one power source on the prime-mover for the harvester.

21. The sugar cane harvester as claimed in claim 20, wherein:

the prime-mover is mounted on a pair of crawler-tracks; or on at least four wheels, where at least one pair of the wheels are steered, or all of the wheels are arranged for skid-steer operation; where the crawler-tracks or wheels have a low- pressure footprint.

22 . The sugar cane harvester as claimed in claim 20, wherein:

the power source is an internal combustion engine, which is operably connected to a transmission for the wheels or crawler-tracks of the prime-mover; and is operably connected to one or more hydraulic pumps to drive associated motors and/or rams for the harvesting apparatus and conveying apparatus

23. The sugar cane harvester as claimed in any one of claims 20 to 22, wherein: the at least one receptacle includes a pair of bins or hoppers selectively movable to enable discharge of the harvested cane stalks from one bin or hopper while the other bin or hopper receives the harvested cane stalks from the conveying apparatus, the bins or hoppers being mounted on the prime-mover for side-tipping by at least one hydraulic ram, or provided on a trailer towed by the prime-mover.

24. The sugar cane harvester as claimed in any one of claims 20 to 23, wherein: the conveying apparatus includes a pair of vertically- spaced stalk conveyors, which are divergent in side view; and where the upper of the stalk conveyors can be raised or lowered to suit different cane stalk lengths.

25. The sugar cane harvester as claimed in claim 24, wherein:

the upper of the stalk conveyors has a pair of combining chains, where the harvested cane stalks are engaged between rearwardly-moving runs of the combining chains; and

the lower of the stalk conveyors has pairs of rotating sprockets or plates, provided at spaced intervals, to engage the harvested cane stalks passing therebetween.

26. The sugar cane harvester as claimed in any one of claims 20 to 25, wherein: the paths of the spikes or blades are substantially perpendicular to the row of cane stalks in top plan view.

27. The stripping apparatus as claimed in claim 4, wherein:

the paths of the spikes or blades are substantially perpendicular to the row of cane stalks in top plan view.