Title of Invention	A CLEANING METHOD FOR A SUGAR-CANE HARVESTING MACHINE AND A SUGAR CANE HARVESTING MACHINE
Abstract	The invention relates to a cleaning method for a sugar-cane harvesting machine and to a sugar-cane harvesting machine operating in accordance therewith, in order to harvest green sugar cane without a reduction in capacity. At the same time, optimum separation of the billets formed from the sugar-cane stalks from the foreign components is ensured.

Full Text

The invention relates to a cleaning method for a sugar-cane harvesting machine/ in which/ by means of a main blower arranged in the lower region of the sugarcane harvesting machine, a cleaning air stream is produced which runs obliquely and upwards and is directed in the direction of the waste chute, and in which, by means of a second deflection blower, an air stream is guided such that foreign components to be separated out are directed through a waste chute. Furthermore, the invention relates to a sugarcane harvesting machine, in particular for carrying out the method according to the invention, which is equipped with rotor separators, a knife-disc device, an inclined conveyor, a comminution device for the stalks, a discharge conveyor, a waste chute and a cleaning chamber having a main blower and a deflection blower to generate and guide a cleaning air stream. Until now it has been usual to set fire to the fields before harvesting sugarcane, in order to burn the leaves and tips. The subsequent harvest is carried out either by hand or by means of appropriately designed sugar-cane harvesting machines. The comminuted stalks are referred to as billets. In order to separate the foreign components, formed by residues of leaves and tips, from the billets, the sugarcane harvesting machines are equipped with two blowers. In this case, axial and radial blowers are used, both blowers of identical construction or else a combination being used. By means of the axial blower, it is also possible to achieve a suction, but it is disadvantageous that as a result the billets can also be sucked up, The invention relates to a cleaning method for a sugar-cane harvesting machine and to a sugar-cane harvesting machine, in which, by means of a main blower arranged in the lower region of the sugar-cane harvesting machine, a cleaning air stream is produced which runs obliquely and upwards and is directed in the direction of the waste chute, and in which, by means of a second deflection blower, an air stream is guided such that foreign components to be separated out are directed through a waste chute. Furthermore, the invention relates to a sugar-cane harvesting machine, in particular for carrying out the method according to the invention, which is equipped with rotor separators, a knife-disc device, an inclined conveyor, a comminution device for the stalks, a discharge conveyor, a waste chute and a cleaning chamber having a main blower and a deflection blower to generate and guide a cleaning air stream. Until now it has been usual to set fire to the fields before harvesting sugar-cane, in order to bum the leaves and tips. The subsequent harvest is carried out either by hand or by means of appropriately designed sugarcane harvesting machines. The comminuted stalks are referred to as billets. In order to separate the foreign components, formed by residues of leaves and tips, from the billets, the sugar-cane harvesting machines are equipped with two blowers. In this case, axial and radial blowers are used, both blowers of identical construction or else a combination being used. By means of the axial blower, it is also possible to achieve a suction, but it is disadvantageous that as a result the billets can also be sucked up, although the axial blower is exclusively intended to suck up the foreign components with the air stream and to feed them to the waste chute. A sugar-cane harvesting machine of this type is known, for example from DE 34 29 204 C2 and DE 33 34 968 Al. The main blower, which in that document is mounted in the lower part of the sugar-cane harvesting machine/ a radial blower. The blower outlet nozzle of the main blower is inclined in the direction of the adjacent discharge chute. Because of their relatively high weight, the billets fall onto the discharge conveyor, the foreign components being entrained by the air stream or being sucked off by the air stream of the axial blower and falling onto the field through the opening of the waste chute. These sugar-cane harvesting machines have been thoroughly tried and tested in practice. However, in the near future more severe environmental regulations are to be expected, which on a world wide scale will forbid burning off being carried out before the harvest, so that accordingly only so-called "green sugar-cane" may be harvested, as a result of which the proportion of foreign components to be separated off will be increased to an extreme extent with respect to the actual sugar-cane. The result of this is that, given the required capacity of a sugar-harvesting machine of known design, the cleaning results are too poor. This can be traced back to the fact that the cleaning spaces or cleaning chambers are too small, so that the time for the separation of the increased amount of foreign components is too short. In addition, it is no longer possible to use an axial blower, since it will be expected that the billets will be sucked up and broken up to a larger extent, so that the losses will be too high. Furthermore, the harvested material will correspondingly be guided in too short a time through an inappropriately small constructional space. The invention is based on the object of indicating a cleaning method and a sugar-cane harvesting machine operating in accordance therewith of the generic types, each of which ensures that, during the harvesting of unburned, green sugar-cane, in spite of the increased throughput, optimum separation of the billets formed from the sugar-cane stalks by comminution from the foreign components is performed using the capacities of the previously known machines. In terms of the method, the ob j ect set is achieved in that the main blower produces a first upstream air stream which initially runs approximately rising from bottom to top, and in that by means of a deflection blower which is functionally associated with the main air stream, via a further air stream generated by the latter, the first air stream is turned in the direction of the waste chute, so that thereafter both the air streams are directed towards the waste chute. In the case of the cleaning method according to the invention, in a further refinement, a plurality of air flows are now used. The first air cleaning stream, directly after the exit from the blower output nozzle, runs directly behind the comminution device arranged at the front in the machine, by which means a substantial separating and cleaning effect is achieved. The second cleaning air stream, which is likewise branched off from the main blower but further to the rear in the machine, can also be viewed as a post-cleaning means, since the cleaning air stream is directed towards the already precleaned billets. In accordance with this principle, still further air streams can be derived from the main blower, it being the case however that a cleaning result which is considerably improved by comparison with the prior art is already achieved using two air streams. In order not to overload the main blower by the additional cleaning air streams, the cleaning air stream can also in each case be assigned a dedicated additional main blower. The cleaning method now runs in three stages. When implementing this cleaning method, an adequately dimensioned cleaning chamber is needed, the volume of which must, for example, be twice as great as in the case of the previously known methods or sugar-cane harvesting machines. This also achieves an adequate time for the separation out of the foreign components. The significant effect can be traced back to the fact that, by means of the first cleaning air stream, in conjunction with the second or further cleaning air streams, the harvested material to be cleaned is kept floating for a longer time, as a result of which the separation out of the foreign components is promoted. Furthermore, a pneumatic conveying effect is achieved, so that, if appropriate, mechanical conveying elements can be dispensed with. Furthermore, the conveying speed is increased. The two air streams also have the effect that the lighter foreign components, essentially formed from the leaves, are conducted upwards and towards the rear. The main cleaning air stream of the main blower should be located at the front, related to the flow direction of the harvested material, in order to supply the necessary energy for conveying the foreign components. A simple, constructive, reliably implementable solution is achieved if the main cleaning air stream and the cleaning air stream are generated by means of a single blower, preferably a radial blower, which has two blower outlet nozzles. In order that the main cleaning air stream is led vertically from the bottom to the top, and the cleaning air stream is directed towards the waste chute, provision is made for the central longitudinal axes of the blower outlet nozzles, if they are extended further, to enclose an acute angle. These central longitudinal axes may intersect inside or outside the contour of the radial blower. In order to be able to adapt the air streams to changing conditions, such as for example given different quantities of material, proportions of leaves etc., provision is made for the quantities of air and/or the velocities of air of the blower to be variable per unit time, and that furthermore the flow directions of the cleaning air stream and deflection air streams emerging from the blower outlet nozzles of the blowers to be variable within prescribed angular ranges. By this means, it is also possible to influence the flow speed, which is increased with decreasing cross-section of the blower outlet nozzles. The object directed to the sugar-cane harvesting machine is achieved in that the main blower has at least two blower outlet nozzles, at least one of the blower outlet nozzles directing a cleaning air stream, on the side facing away from the comminution device, towards the waste chute, in that the second blower outlet nozzle, on the side facing the comminution device, is arranged upright or approximately upright for the main cleaning air stream, with the result that its flow direction runs from bottom to top, essentially vertically, and in that in the upper region of the cleaning chamber a deflection blower is installed in such a way that the main cleaning air stream is led in the direction towards the waste chute. The advantages which are achieved with this machine are essentially the same as in the case of the method according to the main claim. The particular advantage in terms of the design resides further in the fact that the main cleaning air stream and the cleaning air stream are generated by a single blower. However, alternatively it would also be possible for one blower to be installed in each case for the cleaning air stream and for the main cleaning air stream. The cleaning effect of the main air stream is particularly effective, since the flow direction of the chopped sugar-cane is either transverse to the flow direction of the main cleaning air stream or is inclined at a small acute angle with respect to the vertical. For the purpose of the optimum control of the wind speed and of the distribution of the harvested material flow, provision is made for the rotors of the blowers to be coupled to controllable drives, in order to be able to set the rotational speed optimally or to be able to control it during operation. In addition, controllable guide flaps for influencing the flow velocity and the flow direction are pivotably mounted in the blower outlet nozzles of the blowers. In order to prevent losses of the comminution device as far as possible, and to stabilize the main cleaning air stream emerging from the upright blower outlet nozzle, provision is made that a roll with a smooth peripheral surface is mounted, such that it can be driven in rotation, between the comminution device and the upright blower outlet nozzle. The direction of rotation should run opposite to the air stream of the main blower. Since the comminution device normally comprises a pair of chopping rolls, a gap is formed between the smooth roll and the lower chopping roll, which is located at about the same level. In order that no chopped material falls through, provision is made for a sealing element, extending over the width of the chopping device, to be arranged between the comminution device and the conveyor roll. In order to ensure that the cut-off sugar-cane is drawn in reliably, provision is made for the inclined conveyor to comprise a plurality of roll pairs which are arranged one behind another and are rotatably mounted between the comminution device and the knife-disc device. As a result, the cut-off stalks are gripped and drawn in reliably, so that the risk of blockage can be ruled out. In order that the billets, after they have passed through the main cleaning air stream, pass reliably onto the discharge conveyor, provision is made for an elevator, which is arranged above the main blower, to be mounted between the upright blower output nozzle of the main blower and the discharge conveyor. However, this elevator could also be dispensed with if the kinetic energy of the billets were sufficient to reach the discharge conveyor. As already mentioned, the volume of the cleaning chamber in the sugar-cane harvesting machine according to the invention is about twice as large as in the case of conventional machines. In order that the overall height can be reduced when travelling on the road, provision is made for the walls laterally bounding the cleaning space in the upper region to comprise in each case two collapsible half-walls, whose adjacent edges are connected to each other by hinges. When not in use, the two half-walls are moved towards one another, lying flat, at as small a spacing as possible. In order to make this easier for the driver, provision is made for a piston/cylinder unit to be articulated in each case to the lower half-walls, and for the upper edges to be fixed on sliding shoes which can be displaced on vertical guide rods. As a result of the partial reduction in the overall height of the cleaning chamber, a free space is produced. The latter is used in order to move in, at least partially, that portion of the discharge conveyor which projects laterally with respect to the sugar-cane harvesting machine. Provision is therefore made for the discharge conveyor to be formed from a plurality of individual conveyors which can be pivoted about axes lying transverse to the conveying direction. In order that usable chopped material, even if in relatively small quantities, is prevented from being blown through the waste chute onto the field, provision is made for the outlet cross-section of the waste chute to be variable by means of an adjustable slide, depending on the changing conditions in the stock of harvested material, the slide being displaceable upwards from the lower wall of the waste chute. The adjustability of the waste cross-section increases the pressure inside the portion of the machine which is located upstream of the waste chute. The through-flow velocity through the waste chute is reduced thereby. Billets carried by the cleaning wind streams will no longer be thrown away through the waste chute onto the field, but rather, because of the pressure wind relationships being adapted by the slide, will receive a movement path in which they fall reliably towards the discharge conveyor and are transported by the latter towards the accompanying vehicle. The adjustability of the slide can be obtained by hand or else by means of an actuating drive. In order that the intercepted billets are fed reliably to the discharge conveyor, the slide is at an acute angle to the discharge conveyor. The roll which is associated with the upright blower nozzle of the main blower is used for stabilizing the adjacent air stream. For the purpose of further stabilization of the air and mixture flow emerging from the chopping device, provision is made for the upper chopping roll of the comminution device to be followed by a movable boundary surface whose direction of movement is directed towards the main cleaning air stream. This movable boundary surface prevents the parts of the plants emerging from the comminution device, and the other entrained parts of the plants, from flowing in an uncontrolled and turbulent manner through the passage towards the waste chute. This movable boundary surface can be designed in various ways. However, provision is preferably thus made for it to be formed by at least one roll, which can be driven in rotation, or by a circulating belt which is guided over a plurality of rolls. The movement directions of the rolls or of the belt are directed towards the upright main cleaning air stream, in each case referred to the sides facing the main blower. In a further refinement, provision is made that the movable boundary surface is located in the central region between the upright blower outlet nozzle of the main blower and the deflection blower. Accordingly, the present invention provides a cleaning method for a sugar-cane harvesting machine, in which, by means of a main blower arranged in the lower region of the sugar-cane harvesting machine, a cleaning air stress is produced which runs obliquely and upwards and is directed in the direction of a waste chute, and in which, by means of a second deflection blower, an air stress is guided such that the foreign components to be separated out are directed through a waste chute, characterized in that, in the region of the main blower for the cleaning air stream, a preceding main cleaning air stream is generated which initially runs approximately rising from bottom to top, and in that, by means of a deflection blower which is functionally associated with the main cleaning air stream, via second air stream generated by the latter, the first air stream is turned in the direction of the waste chute, so that both air streams are directed towards the waste chute. Accordingly, the present invention also provides a sugar-cane harvesting machine, in particular for carrying out the cleaning method as described above, which is equipped with stalk separators, a knife disc disc device, an inclined conveyor, a comminution device for the stalks, a discharge conveyor and a waste chute and a cleaning chamber having a first main blower and a deflection blower to generate a cleaning air stream, characterized in that the main blower has at least two blower outlet nozzles, at least one of the blower outlet nozzles directing a cleaning air stream, on the side facing away from the comminution device, in the direction of the waste chute, in that the blower outlet nozzle on the side facing the communication device is arranged upright or approximately upright for the main cleaning air stream, with the result that its flow direction runs from bottom to top, essentially vertically, an in that in the upper region of the cleaning chamber the deflection blower is installed in such a way that the main cleaning air stream is led in the direction towards the waste chute. The invention will be explained in more detail with reference to the accompanying drawings, in which, Figure 1 shows a sugar-cane harvesting machine according to the method according to the invention and designed in accordance therewith, in a side view, purely schematically Figure 2 shows a schematic plan view corresponding to Figure 1, Figure 3 shows the upper region of the cleaning chamber in the operating position, Figure 4 shows the upper region according to figure 3 in a lowered position, Figure 5 shows a schematic section transverse to the direction of travel in the folded-in position of the discharge conveyor and Figure 6 shows a sugar-cane harvesting machine in accordance with the method according to the invention, and designed in accordance therewith, in a second embodiment in a side view, purely schematically Figure 1 shows a self-propelled sugar-cane harvesting machine 1, which is designed in accordance with Figure 2 for harvesting two rows of sugar cane. The machine contains a front driving axle 2 and a rear steering axle 3 and four rotor separators 4. In order to cut off the tips, the sugar-cane harvesting machine 1 is also equipped with a tip-cutting mechanism 5, which is not explained in more detail. In order to cut off the stalks at the bottom, it is equipped with a knife-disc device which is formed from circular knife discs 6 which can be driven in rotation and are arranged in pairs. The knife discs 6 are adjoined by an inclined conveyor which, in the exemplary embodiment illustrated, comprises three roll pairs 7 arranged one behind another. These roll pairs 7 are followed by the comminution device in the form of two chopping rolls 8, 9, which can be driven in rotation and are equipped with appropriate chopping knives. Between the driving axle 2 and the steering axle 3 is the cleaning chamber 10, which is bounded at the top by a roof 11 and by lateral walls which in some areas comprise two half-walls 12, 13, which will be further explained with reference to Figures 3 and 4. Located beneath the cleaning chamber 10 is a discharge conveyor 14, which extends so as to discharge laterally and in rising fashion in the form of a multi-part conveyor belt. The cleaning chamber 10 is adjoined by a waste chute 12 with its opening inclined towards the ground. The basic frame 15 of the sugar-cane harvesting machine 1 is located approximately at the level of the steering axle 3. Located between the driving axle 2 and the discharge conveyor 14, directly above the basic frame 15, is a main blower 16, which extends over the entire width of the sugar-cane harvesting machine 1 and is provided, on the side facing the chopping rolls 8, 9, with a blower outlet nozzle 16a which is directed verti cally upwards and, on the side facing the discharge conveyor 14, with a second blower outlet nozzle 16bf which is inclined towards the waste chute 12. The rotor 16c of the main blower 16 is driven in the clockwise direction in a manner not explained in more detail. A main cleaning air stream, which flows from bottom to top and approximately vertically, as indicated by the arrows, is generated by the upright blower outlet nozzle 16a. This main cleaning air stream is penetrated by the chopped material stream. Here, so to say, a transverse stream process is generated. The cleaning air stream emerging from the blower outlet nozzle 16b runs approximately at an angle of 40° towards the discharge conveyor 14. The billets, formed from the sugar-cane stalks by chopping, are thrown by means of an elevator 17 guided over two deflection rolls onto the discharge conveyor 14, the cleaning air stream in this sense performing post-cleaning. This cleaning air stream is then led to the waste chute 12. If the conveyor stream formed by the billets has sufficient kinetic energy, the elevator 17 may also be omitted. The sugar-cane harvesting machine 1 is equipped with a driver's cab 18, which is located approximately above the driving axle 2, offset laterally in relation to the machine longitudinal axis. This cab 18 is adjoined by the cleaning chamber 10. In front of the cleaning chamber 10, at the level of the cab 18, a deflection blower 19 for the main cleaning air stream emerging from the outlet nozzle 16a is installed. The rotor 19a is likewise driven in the clockwise direction. As a result, the main cleaning air stream is deflected approximately by 90° and led over the discharge conveyor 14, the third cleaning stage then being formed analagously. This main cleaning air stream flows into the waste chute 12. The blower outlet nozzles 16a and 16b of the main blower 16 are each equipped with a controlled flap 16d, the actuating drive not being shown. The blower outlet nozzle of the deflection blower 19 is also equipped with a controlled flap 19d, in order to influence the flow velocities and the exit directions. Rotatably mounted between the upright blower outlet nozzle 16a of the main blower 16 and the lower chopping roll 9 is a smooth-surfaced roll 28, whose direction of rotation is directed counter to the air stream of the rotor 16c of the main blower 16, in order to stabilize the main cleaning air stream and in order to reduce or to prevent the losses through the chopping rolls 18, 19. A stationary, wedge-shaped sealing element 27 is mounted between the lower chopping roll 9 and the roll 28, in order that no chopped material passes through the gap. The walls bounding the cleaning chamber 10 at the sides are equipped in the upper region on each side with two half-walls 13 and 13a, which are articulated to one another via hinges 12. The lengths of these half-walls 13, 13a are about twice as large as the width of the discharge conveyor 14. The two vertical end edges are offset by an identical amount in relation to the longitudinal edges of the discharge conveyor 14. A movement unit 21 is articulated to each lower half-wall 13a, on the outside. The vertical end edges of the half-walls 13, 13a are assigned guide rods 22 arranged on the outside on the housing. The roof 23 and the associated, upper edges of the upper half-walls 13 are connected to sliding pieces 24, which are displaceably arranged on the guide rods 22. Figure 4 shows that by extending the piston rods of the movement unit 21, the half-walls 13, 13a are collapsed, and that the roof is lowered. A free space is then produced between the four guide rods 22. Figure 5 shows that when driving on roads the outer end of the discharge conveyor 14 can be pivoted, at least partially, into the free space located between the guide rods 22. To this end, the discharge conveyor 14 comprises a part 14a which is always located within the sugar-cane harvesting machine, a central part 14b and an outer part 14c. In the retracted position, the central part 14b runs vertically and is located still within the contour of the sugar-cane harvesting machine 1• The end 14c runs approximately horizontally inside the said free space. The central part 14b and the end part 14c may be retracted and extended by piston/cylinder units 25, 26. The retracted position is shown with continuous lines in Figure 5, whereas the extended position during the use of the sugar-cane harvesting machine 1 is illustrated with chain-dotted lines. This position of the discharge conveyor 14 is identified by the reference symbol 14'. An intermediate position during retraction is identified by the reference symbol 14'. Figure 6 shows a further embodiment of the sugar-cane harvesting machine 1. A first difference resides in the fact that the outlet cross-section of the waste chute 12 can be varied by means of an adjustable slide 29. The slide 29 may be displaced upwards from the lower wall of the waste chute 12. In the exemplary embodiment illustrated, the slide 29 consists of a sheet-metal profile. It may be displaced from the lower position into an upper position 29', which is indicated with chain-dotted lines. The displacement can be performed manually or by means of an actuating drive. As a result, different conditions in the harvested material stock are taken into account. In the space upstream of the waste chute 12 there is a rise in pressure if the outlet cross-section of the waste chute 12 is reduced, although the flow speed inside the waste chute 12 is reduced. Billets / which without the slide 29 were still thrown out through the lower region onto the field, now strike against the slide 29 and are diverted in the direction of the discharge conveyor 14. It can be seen from Figure 6 that the slide 29 encloses an acute angle with the discharge conveyor 14. As has already been described, the roll 28 associated with the upright blower outlet nozzle 16a of the main blower 16 serves to stabilize the adjacent main cleaning air stream. For the purpose of further stabilization of the flow emerging from the comminution device, this flow being formed from the parts of the plant and the entrained other parts of the plants, which traverse the space to be viewed as a passage in an uncontrolled and turbulent manner, provision is made for the upper chopping roll 8 of the comminution device to be followed by a movable boundary surface 30 whose effective direction of movement is directed towards the main cleaning air stream. This, movable boundary surface is located approximately in the central region between the upright blower outlet nozzle 16a of the main blower 16 and the deflection blower 19. In the exemplary embodiment illustrated, the movable boundary surface is formed by a belt 33 led over two deflection rolls 31, 32, the running direction of the strand which is located facing the main blower 16 being indicated by the arrow. In contrast to the design illustrated, the movable boundary surface 30 could also comprise one or more rolls, but these would have to be driven in such a way that the velocity component of the region which is located facing the main blower 16 runs in the direction of the arrow. The direction of rotation would consequently have to be in the counter clockwise direction, in accordance with the illustration according to Figure 6. or reterence symoois 1 Sugar-cane harvesting machine 2 Driving axle 3 Steering axle 4 Stalk separator 5 Tip-cutting mechanism 6 Knife discs 7 Roll pairs 8 Chopping roll 9 Chopping roll 10 Cleaning chamber 11 Roof 12 Waste chute 13 Half-wall 13a Half-wall 14 Discharge conveyor 14a Part 14b Part 14c Part 15 Basic frame 16 Main blower 16a Blower outlet nozzle 16b Blower outlet nozzle 16c Rotor 29 Slide 16d Flap 30 Movable boundary surface 17 Elevator 31 Deflection roll 18 Driver's cab 32 Deflection roll 19 Deflection blower 33 Belt 19a Rotor 19d Flap 20 Hinge 21 Movement unit 22 Guide rods 23 Roof 24 Sliding piece 25 Piston/cylinder unit 26 Piston/cylinder unit 27 Sealing element 28 Roll WE CLAIM: 1. A cleaning method for a sugar-cane harvesting machine, in which, by means of a main blower arranged in the lower region of the sugar-cane harvesting machine, a cleaning air stream is produced which runs obliquely and upwards and is directed in the direction of a waste chute, and in which, by means of a second deflection blower, an air stream is guided such that the foreign components to be separated out are directed through a waste chute, characterized in that, in the region of the main blower (16) for the cleaning air stream, a preceding main cleaning air stream is generated which initially runs approximately rising from bottom to top, and in that, by means of a deflection blower (19) which is functionally associated with the main cleaning air stream, via second air stream generated by the latter, the first air stream is turned in the direction of the waste chute (12), so that both air streams are directed towards the waste chute (12). 2. The cleaning method according to claim 1, wherein the main cleaning air stream and at least one further cleaning air stream are generated by means of a single main blower (16), preferably a radial blower, which has at least two blower outlet nozzles (16a, 16b). 3. The cleaning method according to claims 1 and 2, wherein at least one further cleaning air stream is generated by said deflection blower. 4. The cleaning method according to one or more of the preceding claims, wherein the central longitudinal axes of the blower outlet nozzles (16a, 16b), if they are extended further, enclose an acute angle (@). 5. The cleaning method according to one or more of the preceding claims 1 to 4, wherein the quantities of air and/or velocities of air from the main blower or blowers (16) and the deflection blower (19) can be varied per unit time. 6. The cleaning method according to one or more of the preceding claims 1 to 5, wherein the flow directions of the cleaning air stream and deflection air streams emerging from the blower outlet nozzles (16a, 16b) of the main blower (16) and the deflection blower (19) can be varied within prescribed angular ranges. 7. A sugar-cane harvesting machine, in particular for carrying out the cleaning method according to claim 1, which is equipped with stalk separators, a knife disc device, an inclined conveyor, a comminution device for the stalks, a discharge conveyor and a waste chute and a cleaning chamber having a first main blower and a deflection blower to generate a cleaning air stream, characterized in that the main blower (16) has at least two blower outlet nozzles (16a, 16b), at least one of the blower outlet nozzles (16b) directing a cleaning air stream, on the side facing away from the comminution device (8, 9), in the direction of the waste chute, in that the blower outlet nozzle (16a) on the side facing the comminution device (8, 9) is arranged upright or approximately upright for the main cleaning air stream, with the result that its flow direction runs from bottom to top, essentially vertically, an in that in the upper region of the cleaning chamber (10) the deflection blower (19) is installed in such a way that the main cleaning air stream is led in the direction towards the waste chute (12). 8. The sugar-cane harvesting machine according to claim 7, wherein the rotors (16c and 19a) of the main blower (16) and of the deflection blower (19) are coupled to controllable drives. 9. The sugar-cane harvesting machine according to claim 7, wherein controllable guide flaps (16d, 19d) for influencing the flow velocity and the flow direction are pivotably mounted in the blower outlet nozzles (16a, 16b) of the main blower (16) and in the blower outlet nozzles of the deflection blower (19). 10. The sugar-cane harvesting machine according to claim 7, wherein a roll (28) with a smooth peripheral surface, which stabilizes the emergent air stream, is mounted, such that it can be driven in rotation, between the comminution device (8, 9) and the upright blower outlet nozzle (16a) of the main blower (16). 11. The sugar-cane harvesting machine according to claim 10, wherein the direction of rotation of the roll (28) is directed counter to the air stream of the main blower (16) at its blower outlet nozzle (16a). 12. The sugar-cane harvesting machine according to claim 10, wherein a sealing element (27) is arranged between the lower chopping roll (9) of the comminution device and the roll (28). 13. The sugar-cane harvesting machine according to one or more of the preceding claims 7 to 12, wherein the inclined conveyor comprises a plurality of roll pairs (7) which are arranged one behind another and are rotatably mounted between the comminution device (8, 9) and the knife-disc device (6). 14. The sugar-cane harvesting machine according to one or more of the preceding claims 7 to 13, wherein an elevator (17) for the billets, which is arranged above the main blower (16), is mounted between the upright blower outlet nozzle (16a) of the main blower (16) and the discharge conveyor (14). 15. The sugar-cane harvesting machine according to one or more of the preceding claims 7 to 12, wherein the cleaning chamber (10) has5 in the upper region of laterally bounding walls, two collapsible half-walls (13, 13 a) in each case, whose adjacent edges are articulated to each other by hinges (20). 16. The sugar-cane harvesting machine according to claim 15, wherein a movement unit (21) is in each case articulated to the lower half-walls (13a), and in that the upper edges of all the half-walls (13) engage on sliding shoes (24) which can be displaced on vertical guide rods (22) and to which the roof (23) is fixed. 17. The sugar-cane harvesting machine according to one of claims 15 and 16, wherein the discharge conveyor (14) is formed by a plurality of individual conveyors (14a, 14b, 14c), the portions (14b) and (14c) of which can be pivoted by means of movement units (25, 26) about axes lying transverse to the conveying direction. 18. The sugar-cane harvesting machine according to claim 7, wherein the outlet cross-section of the waste chute (12) can be varied by means of an adjustable slide (29), the slide being displaceable from the lower wall towards the opposite upper wall of the waste chute (12). 19. The sugar-cane harvesting machine according to claim 18, wherein the slide (29) encloses an acute angle with the discharge conveyor (14). 20. The sugar-cane harvesting machine according to claim 7, wherein the upper chopping roll (8) of the comminution device is followed by a movable boundary surface (30) whose effective direction of movement is directed towards the main cleaning air stream. 21. The sugar-cane harvesting machine according to claim 20, wherein the movable boundary surface (30) is formed by at least one roll which can be driven in rotation, or by a belt (33) led over a plurality of rolls (31, 32). 22. The sugar-cane harvesting machine according to claim 20 or 21, wherein the movable boundary surface (30) is located in the central region between the upright blower outlet nozzle (16a) of the main blower (16) and the deflection blower (19). 23. A cleaning method for a sugar-cane harvesting machine substantially as herein described with reference to the accompanying drawings. 24. A sugar-cane harvesting machine substantially as herein described with reference to the accompanying drawings.

Documents:

1770-mas-1997 form-19.pdf

1770-mas-1997 form-2.pdf

1770-mas-1997 form-6.pdf

1770-mas-1997 others.pdf

1770-mas-1997 petition.pdf

1770-mas-1997- abstract.pdf

1770-mas-1997- claims.pdf

1770-mas-1997- correspondence others.pdf

1770-mas-1997- correspondence po.pdf

1770-mas-1997- description complete.pdf

1770-mas-1997- drawings.pdf

1770-mas-1997- form 1.pdf

1770-mas-1997- form 3.pdf

1770-mas-1997- form 4.pdf