AU746642B2 - Sugar cane harvester - Google Patents

Description

l P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 4* S

S

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "SUGAR CANE HARVESTER" The following statement is a full description of this invention, including the best method of performing it known to me: 2 TITLE: SUGAR CANE HARVESTER FIELD OF THE INVENTION THIS INVENTION relates to improvements which apply to sugar cane harvesters of the type wherein billets of cane are produced, separated from trash.

BACKGROUND ART Sugar cane harvesters have been produced by which cane is topped, cut at the base and diced into billets for delivery to a mill. A harvester of this kind is seen in the specification No. 505743 10 (23614/77) to the present applicant. The process of harvesting can result in the collection of a good deal of trash along with the billets, the trash being cane leaves, weeds, stones and dirt. An object in design of harvesters is the separation of trash of the above kind so that the product at the mill is as free of trash as is possible. There is an on-going need for ever more efficient harvesters which not only separate trash effectively but do so efficiently without slowing harvesting, or increasing the fuel requirements to power the harvester.

OBJECTS OF THE INVENTION The general object of the present invention is to provide improvements which enhance the operation of mechanical, motorised, sugar cane harvesters of the above type wherein billets of cane are produced and collected, the collection being minimised trash content.

A preferred object is to provide a variable height suspension to a sugar cane harvester to enable the setting of the cutting blade height.

3 In a broad aspect, the present invention resides in a variable height suspension unit for use with a sugar cane harvester and other vehicles which comprises: a piston rod mountable on a vehicle frame at top and bottom thereof; a cylinder which is slidably and rotatably mounted about the piston;' steering means engageable with the cylinder to rotate it about the piston rod; and 10 axle mounting means mounted to the cylinder to support an axle and associated wheel; characterised in that: hydraulic means is provided to slidably move the cylinder *relative to the piston rod to raise and lower the frame relative to the axle and wheel.

The above defined suspension assembly enables setting of the height of the cane base cutter.

Another aspect of the above is the variation in cane base cutter height as the harvester travels over rough ground. This effect is minimised by putting the cutter between the front wheels.

In its use in a sugar cane harvester, the above defined variable height unit enables the height of a cane base cutter to be set to an optimum height chosen to maximise cut cane lengths but not be too low to raise stones and dirt from the cane base to contaminate the cut cane. It also permits simplicity in design and operation.

BRIEF DESCRIPTION OF THE DRAWINGS 4 To enable the invention to be more fully understood, various preferred embodiments will now be described with reference to the accompanying drawings in which: FIG. 1 is a schematic side view of a harvester in accordance with the invention; FIG. 2 is a schematic sectional view of a cleaning roller for the harvester; FIG. 3 is a sectional view through a separation chamber .for the harvester; and FIG. 4 is a sectional side view of a variable height suspension unit in accordance with the present invention.

PREFERRED EMBODIMENTS The sugar cane harvester 100 is of generally ~conventional type such as is set out in 505743, which can be mounted on front wheels 10 and rear wheels 11, and which can have a topping cutter 12A carried by a vertically adjustable frame 12, a pair of gathering arms 13 can extend forwardly to pass to both sides of a row of cane as the harvester advances, and rotary crop lifters (not shown) on the gathering arms 13 can be pick up cane, which is cut ideally at or near ground level by a pair of laterally aligned counter-rotated base cutters 15. The base cutters are located between the front wheels beneath the frame of the apparatus. Their height is set by the means described below.

Above the rear parts of the base cutters 15 can be a floating or vertically movable transverse roller 16 with, ideally, radiating vanes which are serrated at their outer edges, this roller being driven in a counter-clockwise direction in the sense of the drawing so as to impel cane stalks, cut by the base cutters, rearwardly through the harvester, butt ends first.

The cut cane stalks are conveyed, from the base cutter 15 and floating roller 16, to a chopping cutter assembly at 17 between the upper feed rollers 18 and the lower feed rollers 19 of a feed conveyor system. The upper and lower feed rollers are substantially similar, each having a pair of end discs (as described in 505743) secured on the ends of a drum of lesser diameter with a 10 series of vanes radiating from the drum and being secured to the end discs. The outer edges of the vanes are ideally serrated.

The shafts of the lower feed rollers 19 are preferably rotatably mounted in bearings secured to the main frame of the S. harvester. The upper feed rollers 18 can be driven, for example, by a chain drive (not shown) so that they may all be rotated in the same direction and at the same speed. The lower feed rollers 19 are preferably driven at the same speed as, but in opposite angular direction to, the upper feed rollers, so that the upper and lower feed rollers will feed cane rearwardly between them.

The gap between the first, second and third feed rollers is left open and between each pair of succeeding lower feed rollers 19 there is provided a transverse cleaning roller 25 consisting of a square section drum to which are secured vanes as described below.

Each of the cleaning rollers is basically similar in geometry consisting, as shown in FIG. 2, of a square drum 26 (typically RHS at 76 x 76 x 7mm) to the ends of which are secured 6 coaxial end discs (not shown but similar to those used in 505743) of greater diameter, an axle (not shown) being secured coaxially with the drum and end discs, and a series of equally spaced radial vanes 29 being secured to the drum and end discs. The vanes 29 may be flat or serrated at their outer edges and they extend outwardly beyond the end discs of the roller (to pinch trash, in use, against the drums of the lower feed rollers). The vanes 29 are formed of rubber belting (typically 1 2mm thick), of plastics material, or any material •which is flexible and resilient. When a rock or stick is conveyed between the upper and lower feed rollers, the vanes can flex to prevent the obstruction from jamming or damaging the vanes 29.

The vanes may be bolted to the square section drum 26 with bolts 28 clamping the vanes 29 beneath plates 27 to the drum 26.

The axes of the shafts of the lower feed rollers 19 may lie in a plane which inclines upwardly from front to rear. The axes of the cleaning rollers 25 ideally lie in a plane parallel to and below a plane containing the axes of the lower feed rollers shafts, and the cleaning rollers are preferably driven at the same speed as, but in the opposite direction to, that of the lower feed rollers 19. The lower feed rollers and the interposed cleaning rollers are so arranged that their end discs 20 and 27 closely approach, and the vanes 21 of the lower feed rollers are in intermeshing relationship with the vanes 29 of the cleaning rollers to thus avoid fouling as the lower feed rollers and cleaning rollers are counter-rotated. The rearmost of the lower feed rollers may be chain driven from the drive shaft of a chopping cutter 17 (see FIG. and meshing of gears on their shafts may be 7 the means whereby to drive the alternating cleaning and lower feed rollers as far as the second feed roller from the front, from the shaft of which the foremost lower feed roller is chain driven.

The apparatus will be found to be particularly effective in cleaning harvested cane, including mature cane in which the amount of hanging trash is substantial, and is likely to have fallen to the bases of the cane stools. The cane stalks are cut by the base cutters and are fed, butt ends first, under the upper feed rollers 18 and .:.over the lower feed rollers 19. Much of the leafy matter will be 10 pinched against the lower feed rollers or caught by the rotating cleaning rollers 25, driven in opposite direction to the lower feed rollers 19, and will be pulled down from the cane stalks and discharged to the ground. It is found, too, that the counter-rotation of the lower feed rollers 19 and the cleaning rollers 25 causes a strong down-draft of air, which materially assists in cleaning of the cane. The cleaning rollers are so arranged at a lower plane that they do not interfere with the feeding of the cane stalks to the chopping assembly 17, despite their reverse rotation.

The apparatus is very efficient, too, in removing stones and suckers from the butt end parts of the stalks as a result of the pinching effect of feed and cleaning rollers. The intermeshing arrangement of the vanes of the lower feed rollers and the cleaning rollers, in removing a substantial proportion of the trash from the cane before the cane is chopped into billets in the chopping assembly 17, and elevated by the harvester elevator 101 will greatly reduce the load on the other cleaning components of the harvester, associated 8 usually with the elevating and discharging system.

Referring back to FIG. 1 and FIG. 3, from the chopping cutter 17, the cane billets (and any remaining trash) are conveyed by rollers 102 to the separation chamber 103. A conical billet hopper s 101a is spaced a small distance below the separation chamber and directs the cane billets to the elevator 101. A trash extractor 104, with a rotatable hood 105, and fan is connected to the upper end of theseparation chamber 103. The separation chamber 103 has an enlarged central portion 106 and the cleaning air is drawn into the separation chamber 103 through the air gap 107 between the separation chamber 103 bottom and the elevator billet hopper 101a as well as the side of the transport roller (107a). This is seen in section in FIG. 3. Tests have shown that the arrangement provides highly efficient cleaning of the trash from the cane billets. The larger the chamber 106, the better. However, other aspects of the harvester will intrude to limit the chamber size. In operation of the apparatus, billets are thrown across the chamber to impact on its rear wall to bounce back and this action is believed to break any interlocking of billets by trash to enable trash to rise on the air current with the heavier billets freed to fall through the stronger air stream at the base of the chamber.

Referring now to FIG. 4, at least the front wheels 10 are provided with variable height suspension units 200 to enable the cutting height of the base cutter 15 to be adjusted. A double ended piston rod 203 is mounted in the harvester attached to its frame via suitable mounting brackets 214. A cylinder 201 is slidably, rotatably 9 journalled in upper and lower bushes 204, 205 with seals 206. A band 207, with seal 208, on the cylinder 201 divides the cylinder into two variable volume chambers 209, 210. An axle mounting plate 211, with reinforcing bracket 212, is provided at the lower end of the cylinder 201 to mount a stub-axle and wheel 10 (not shown). A hydraulic motor mounting plate 213 enables a hydraulic motor (not shown) to be provided to drive the wheel 10. A steering arm 202, to rotate the cylinder 201, is connected to the upper end thereof.

By selective variation of the volumes of the chambers 209, 210, the frame (and piston 203) can be raised or lowered relative to the wheel 10 (and cylinder 201). This is done hydraulically .•.00using suitably configured valving to the chambers of the suspension units at each side of the vehicle. Whilst wheels are shown in the above-referenced figures, it will be appreciated that these can be replaced with tracks.

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

Claims (3)

1. A variable height suspension unit for use with a sugar cane harvester and other like vehicles which comprises: a piston rod mountable on a vehicle frame; a cylinder encasing the piston rod, the piston rod extending through the cylinder which is slidably, rotatably mounted thereon; steering means engageable with the cylinder to rotate o the cylinder; and axle mounting means mounted to the cylinder to support an axle and associated wheel; characterised in that: hydraulic means is provided to slidably move the cylinder relative to the piston rod to raise and lower the frame relative to the axle and wheel.

2. A variable height suspension unit as claimed in Claim 1 wherein the piston rod is configured to divide the chamber between the piston and cylinder into a plurality of chambers by which hydraulic fluid passed selectively thereto effects the movement of the cylinder along the piston rod.

3. A suspension unit substantially as hereinbefore described with reference to the drawings. DATED this twenty-seventh day of March 2000. JOSEPH MICHAEL MIZZI By his Patent Attorneys FISHER ADAMS KELLY