WO2002074063A1

WO2002074063A1 - Combine harvester

Info

Publication number: WO2002074063A1
Application number: PCT/EP2002/000687
Authority: WO
Inventors: Andrie Visagie; Thomas Barrelmeyer
Original assignee: Claas Selbstfahrende Erntemaschinen Gmbh
Priority date: 2001-03-19
Filing date: 2002-01-24
Publication date: 2002-09-26
Also published as: UA76981C2; RU2279207C2; GB0106722D0

Abstract

This invention refers to a combine harvester with a rotor housing which is positioned in a lengthwise direction and which comprises a separation rotor (24) inside of the rotor housing and sucking blower (36) means arranged at the discharge end of the rotor housing, whereby the shaft of the sucking blower means is coaxially towards the shaft of the separation rotor. To allow a better adaption of the rotational speeds of the separation rotors and the sucking blower units to the prevailing harvesting conditions, it is suggested that the rotational speeds of a sucking blower unit and the corresponding separation rotor are variably adjustable relative to each other by adjusting their drive mean.

Description

Combine Harvester

The present invention relates to a combine harvester with at least one separation unit comprising a rotary driven separation rotor arranged in a rotor housing with a feeding zone where harvested material is fed into the rotor housing a separation zone with sieve means arranged in the rotor housing of said separation zone, a discharge zone which is located at the discharge end of the rotor housing and a sucking blower unit which sucks an air flow stream at least through the sieve means into the separation zone and the discharge zone, and a grain collecting element arranged in some distance towards the sieve means, all arranged such that a part of the air flow stream is sucked into the separation zone from the space between the sieve means and the grain collecting element.

Such a separation unit is known from PCT/US 97/02432. In that separation unit, the sucking blower units and the working elements of the separation rotors are mounted on one single shaft. Because a high rotational speed of the sucking blower unit is needed to achieve an air flow stream which is strong enough to take chaff particles with it, also the tools of the separation rotor in the separation zone are moving with a corresponding high rotational speed. In average harvesting conditions this arrangement works in a satisfactory way, however, under certain conditions the kernel breakage is too high, and also the damage of the straw is too high. It is also difficult to adapt this arrangement precisely towards the prevailing special harvesting conditions.

From DE 37 17 501 it is known to fix a threshing drum on a hollow shaft, which is rotatably and coaxially positioned on the first third section of a rigid shaft which fully projects through the total length of a cylindrical rotor housing, and on the other two thirds of the shaft separation tools are fixed on it. By this arrangement it is possible to operate the threshing drum and the separation rotor with different rotational speeds.

It is the subject of this invention to achieve an improvement in the separation process without limiting the performance level of the sucking blower unit. The objects and advantages of this invention can be achieved, if the rotational speeds of a sucking blower unit and the corresponding separation rotor are variably adjustable relative to each other by adjusting their drive means.

By a variation of the relation between the rotational speeds of a sucking blower unit and the corresponding separation rotor it is possible to operate the sucking blower unit with an optimized capacity, whereas the separation rotor may be operated with less rotational speed to cause less losses, damage to the straw or kernel breakage of kernels kicked back into the rotor housing. For using this invention, the rotational speed of the sucking blower unit or the separation rotor may be adjustable, or the rotational speed of both elements may be varied. According to this invention, there must be a split in the drivetrain from the engine towards a sucking blower unit on the one side and the corresponding separation rotor on the other side, and at least in one splitted path there are elements necessary which allow a variation of the rotational speed of that shaft. To operate the sticking blower unit with an optimized capacity means, that its rotational speed in relation towards the rotational speed of the separation rotor is chosen on a level, where the amount of grain kernels sucked out of the rotor housing is kept on a low level, however, the sucking air flow stream is still strong enough to keep most of the chaff fraction inside of the rotor housing and the separation rotor and the sucking blower unit may be operated with speeds which do not damage the straw more than necessary and which do not cause more kernel breakage than necessary. With an opportunity of adjustment, of course it is possible to give one or more of those aspects mentioned more or less priority, and the setting of the rotational speeds of the shafts can be adapted to the desired result in the actual harvesting process. For example, when harvesting wet grain, a stronger air flow stream may be desired as in dry conditions, or for harvesting rapeseed a gentler air flow stream is required as for harvesting maize to achieve satisfactory separation of kernels on a low level of losses.

In a preferred embodiment, the shafts of a sucking blower unit and the corresponding., separation rotor are coaxially arranged, one of said shafts is made as a hollow shaft, and the other shaft is projecting through the hollow shaft. This arrangement is cheap to manufacture and does not require much space in the combine harvester.

According to a further embodiment, the rotational speed of at least a sucking blower unit is variably adjustable. This means, that the respective separation rotor is driven with a constant rotational speed, and the speed of the sucking blower unit can be adjusted to the prevailing harvesting conditions. Of course, the variation of the rotational speeds of the sucking blower units may be referred to just one up to all sucking blower units, just as it fits into the concept of the respective combine harvester. This arrangement keeps the costs low.

It is also suggested that the rotational speed of either the sucking blower unit or the separation rotor is adjustable by varying the working speed of the engine. Today, most diesel engines of harvesting machines are controlled by computer elements. Such computer elements control for example the rpm of the engine, the load under which the engine is operated, they determine the time and amount of fuel to be injected into the combustion chambers, they control the wastegate of the turbocharger, and they are connected with other computerized controllers of the harvesting machine, e.g, by BUS- systems, to exchange data about settings of the machine or other parameters or working conditions. It is easy to define certain parameters which urge the computer elements to run the engine with higher or lower speed. To save fuel, it is advantageous to rein the engine with lower speed if the amount of harvested good is not so high that the full power of the engine is required. In another example, it might be advantageous, if a sensor detects a drop of the rotational speed of the separation rotor due to an overload, to increase the rotational speed of the separation rotor by increasing the speed of the engine to overcome the overload condition without a breakdown of the working process. Of course, a reduction especially of the rotational speed of the separation rotor by reducing the engine speed - or by other speed variations accordingly to this invention - might also be beneficial for a reduction of kernel breakage, or a functional improvement and a reduction of losses when the combine harvester starts to harvest a new roe of crop, or when it runs out of a row when it reaches the headline. Due to the rotating cleaning process and the air flow stream support the performance of the combine harvester is not is adversely affected by a reduction of the engine speed as a conventional combine with sieve cleaning would be.

According to another embodiment, there is a first separation unit connected with a second separation unit for cleaning the grain fraction separated in the first separation unit, the shafts of the separation rotors and the sucking blower units of both separation units are driven from one initial driving shaft with at least three discs being fixed on said initial driving shaft, at least one of said three discs being a variator disc. With this concept a cheap and simple solution is available to vary the relation of rotational speeds of the separation rotors and the sucking blower units. V-belt drives are commonly used in harvesting machines and easy to sen/ice, and variators are sufficient for adjusting the rotational speeds of shafts in a certain range of transmission ratios, as long, as the power to be transmitted is not out of range of the variators.

To increase the transmission ratio between the initial driving shaft and the shafts of the separation rotor and sucking blower unit, it is advantageous if besides an initial driving shaft there is an intermediate shaft with at least one variator disc fixed on it. With a bigger spread of transmission ratio it is even possible to maintain a high speed level of the sucking blower unit if the engine speed is lowered.

It is also advantageous if the shaft of a separation rotor projects through the full length of its rotor housing and at its front end there are means to transmit power for operating other working elements of the combine harvester. By this arrangement, additional power transmission means can be saved for driving the feeding elements inside of the feeder house or for driving the cutterbar. It is also possible to attach hydraulic pumps or electric generators to the PTO of the shaft, and to use this power for driving the wheels, operating brakes, operate the unloading auger, etc.

Instead of a mechanical transmission of power, it is also possible to drive at least one shaft of a separation rotor or a sucking blower unit by a hydraulic or electric motor with a variable driving speed. The power level of such components is increasing and their costs are shrinking, so that such components could be useful for variation of rotational speeds.

The invention is now described in more detail by virtue of drawings. In the attached drawings the following aspects can be seen:

Fig. 1 shows a side-view upon a self-propelled combine harvester,

Fig.2 shows one possible embodiment of a drivetrain concept for driving the separation rotor and sucking blower unit,

Fig. 3 shows a different concept for the drivetrain, Fig. 4 shows a drivetrain concept with hydraulic or electric motors for altering the rotational speed of certain shafts.

A combine harvester 2 shown in figure 1 is equipped with a driver's cabin 4, an engine 6 with a cooling system 8, a front wheel 10 with a rotational axis 12, a rearwheel 14, a cutterbar 16, and a feeder house 18, which distributes the harvested material from the cutterbar 16 into the feeding opening 20 of the rotor housing 22, which is part of a sepa ration unit. Inside of the rotor housing 22 there is arranged a separation rotor 24 which is rotatably driven by driving elements 26, here shown as pulley drives, from the power of engine 6. Seen along the rotational axis of the separation rotor 24 from the feeding opening 20 towards the discharge end 28 of the rotor housing 22, the front section of the separation rotor 24 comprises auger blades 30 which approximately define the length of the feeding zone where the harvested material is fed into the rotor housing 22. The middle and rearward section of the separation rotor 24 is equipped with beater plates 32 which approximately define the length of the separation zone along the length of the rotor housing 22. It is noted here that the tools for feeding the harvested material into the rotor housing and threshing and separating the harvested material may also be different from auger blades or beater plates, they are mentioned here just as examples. Of course an expert could also choose other tools which he is aware of and which serve his desired function. The bottom portion of rotor housing 22 comprises of sieve means 34, through which grain kernels and chaff may exit the rotor housing 22. The sucking blower unit 36 sucks an air flow stream at least through the sieve means into the separation zone of the rotor housing 22 and from there towards the discharge zone 28 and out of the rotor housing 22 and out of the combine harvester 2. The sucking blower unit

36 is connected in its function towards the separation rotor 24. Rotor housing 22, sepa ration rotor 24 and sucking blower unit 36 together from the basic components of a separation unit. Grain kernels which exit the rotor housing 22 through the openings of sieve means 34 fall at least partially on the grain collecting element 38 which guides the grain kernels by gravitational forces towards the grain collecting auger 40, which distributes the collected grain into a grain conveyor - not shown-, which feeds the grain into the grain tank 42. The air flow stream generated by the sucking blower 36 is moving through the intermediate space between the sieve means 34 and the grain collecting element 38. The description above refers to the function of a single separation unit, however, it is to be understood that of course there may be arranged two separation units as described side by side in a combine harvester, and instead of conventional sieve means there may be one or more additional separation units as described in its basic function above for a further cleaning of the separated grain, they should then be arranged underneath the first separation units.

The inclined arrangement of rotor housing 22 and the separation rotor 24, which is arranged inside of rotor housing 22, by more than 30° towards the horizontal plane brings some advantages. First of all, it reduces the speed of the harvested material inside of the rotor housing towards the discharge end 28, so that it rotates inside of the rotor housing 22 along a longer travelling path with more opportunities for separating grain kernels. Due to the fact that the gravitational forces are acting with more effect upon the heavier fractions of the harvested material like the grain kernels, they tend to move slower through the rotor housing 22, which brings some separational effect upon them in relation to the lighter fractions of the harvested material like straw or chaff. An additional advantage is that the grain can be collected by simple grain collecting elements 38, which may be formed in the shape of a chute, an transported towards the collecting auger without any further driven elements. Also for using the second separation rotor 44 as a cleaning apparatus for the fraction of grain kernels and chaff which has exited the rotor housing 22, it is advantageous to have an inclined arrangement of the rotor housing 22, because the air flow stream which is moving along the outer surface of the sieve means 34 towards the sucking blower unit 36 cannot suck the grain kernels upwardly very easily due to their weight, so that they tend to fall either onto the grain collecting element 38 or into the second grain exit towards the second separation rotor 44. Also the second separation rotor 44 is combined for its function with a sucking blower unit 54 which generates an air flow stream comparable to the air flow stream generated by the sucking blower unit 36.

The feeder house 18 contains at least two rotation elements, one front rotating element 46 and one rear rotating element 48. The shape of floor 50 of the feeder housing 18 is partially adapted to the circumference of the rotating elements 46, 48. In the region where the arrow 20 points to the line which symbolizes the crosswisely arranged cylindrical shape of the feeder house 18 which houses the rear rotating element 48 in the region of its discharge end, there may also be located the feeding opening of the rotor housing 22. The crosswisely arranged cylindrical shape of the feeder house 18 cuts into the tipper half of the lengthwisely arranged substantially cylindrical shape of the rotor housing 22. The rotating energy of the separation rotor 24, 44 can be transmitted to subordinated elements, which is symbolized by arrow 52.

If the rotor housing 22 is arranged in the combine harvester 2 as described, it is possible to position the engine 6 in a location also in the top rear half portion of the combine harvester 2 behind the rear end of the rotor housing 22. This is advantageous because the power of the engine doesn't need to be transported over long distances towards the separation rotor 24, which saves costs and weight. The high arrangement of the engine also avoids that the cooling system sucks in too many straw which is blown out in a downward and rearward direction by the sucking blower means 36 and the blower of the second separation unit. The power necessary to drive the cutterbar 16 and the feeding elements 46, 48 arranged inside of the feeder house 18 or other working components or generators of hydraulic pressure or electrical energy may be transmitted by the shaft of separation rotor 24 or 44 from the rear to the front of the combine harvester 2. This saves additional drive train elements and it keeps the width of the combine harvester 2 slim. The PTO stubble shaft of the separation rotors 24, 44 may be equipped with toothed wheels which transfer the rotating energy to subordinated shafts, hydraulic pumps, electric generators, gearboxes or the like. For the sake of simplified demonstration, the possibility of driving any other components is indicated by arrow 52.

In the triangle defined b the upper half of the rotor housing 22, the rear wall of the cabin 4 and the top margin of the combine harvester 2, it is easy to accommodate the grain tank 42. If there is only one separation rotor contained in the rotor housing (two in a side-by-side arrangement are possible), the space of the grain tank 42 may even reach downwardly along the sides of rotor housing 22 so that it is designed like a saddle tank.

To achieve enough space to place the front end of rotor housing 22 as low as possible, it is advantageous to avoid a rigid front axle or a crosswiselv arranged beam of the machine frame in the region proximate to the front wheel. To drive that front wheels, small hydraulic or electric motors can be placed next to each wheel so that one motor drives one wheel. In figure 2 an example for the basic concept of a drivetrain system according to this invention is shown. From the crankshaft of engine 6 a pulley drive 100, 102 with an intermediate shaft 104 is directed to drive the grain collecting auger 40, the grin conveyor and other possible components. On the other side of the engine 6 an extension of the crankshaft is connected with a power unit 106, which could be an electric Generator or a hydraulic pump. The pulley drive 108 transmits the power of the engine 6 to the main gearbox 110. From the main gearbox 110 the power is transmitted upon the initial driving shaft 112 for driving the sucking blower units 36, 54 and the separation rotors 24, 44.

The power for driving shafts 118, 120 is transmitted by the pulley drives 114, 116. The disks for driving the pulley drives 114, 116 are rigid disks which do not allow any variation of the ratio of the rotational speeds. So the rotational speed of shafts 118, 120 is in a firm relation, and it can only be varied, if other disks with different diameters are mounted on the initial driving shaft 112. It is noted that the second separation unit for cleaning the grain which has been separated in the first separation unit consists of the separation rotor 44 and the sucking blower unit 54. In the embodiment shown in figure 2 the separation rotor 44 and the sucking blower unit 54 are fixed on the same shaft, so that they are rotating with the same rotational speed. In the first separation unit the separation rotor 24 and the sucking blower unit 36 are not arranged on the same shaft, only separation rotor 24 is fixed on shaft 120. For driving the sucking blower unit 36, a variator disc 122 is fixed on the initial driving shaft 112, and by operating the variator disc 122 the transmission ratio for driving the V-belt 124 is changed. Which size of the variator discs 122, 126 and also the other discs in general also for other embodiments is required, and which transmission ratio shall be provided by the variator discs, must be decided by the engineer who is designing the layout of the combine. The choice of dimensions and transmission ratios is dependant from the required rotational speeds of the respective shafts for providing the best function of the components driven by them. Variator disc 126 is rigidly connected with hollow shaft 128, through which shaft 120 is_. guided. On hollow shaft 128 the blades of sucking blower unit 36 are welded upon.

In the example shown in figure 2 there is only one variator disc 122 fixed on the initial drive shaft 112, which varies the rotational speed of the sucking blower unit 36 of the first separation unit. Of course, in alternative concepts not shown in figure 2 it is also possible to only vary the rotational speed of the sucking blower unit 54 of the second separation unit and all other shafts are driven with fixed relations of their rotational speeds, or to add a second variator disc to initial drive shaft 112, to fix the sucking blower unit 54 on a hollow shaft coaxially arranged on shaft 118, and to drive this additional hollow shaft by the second variator disc, so that both separation rotors 24, 44 are driven in a fixed relation, and the sucking blower units 36, 54 are both variably driven by variator discs. It is also possible to drive one or more sucking blower units 36, 54 constantly from the initial drive shaft 112, and to vary the rotational speed of one or both of shafts 118, 120. Though being still within the scope of this invention, the disadvantage of this concept is that usually a separation rotor consumes more power than a sucking blower unit, and that makes the variator discs heavier than in concepts with variable sucking blower units.

Shaft 120 projects completely through the rotor housing 22, and at its front end there is a gearbox 130 shown as an embodiment of the prior mentioned arrow 52 in figure 1. From this gearbox 130 one shaft is driving the pulley drive 132 to bring the rotating element 48 into rotational movement. Pulley drive 34 transmits the power to rotating element 46, so that all feeding elements of feeder house 18 are driven from shaft 120. Additionally, a disc or toothed wheel 136 can be fixed on the shaft of rotating element 46, so that from this disc or toothed wheel 136 also the cutterbar 6 can be driven. From gearbox 130 power can be transmitted to the power unit 138, which can be used to generate electric or hydraulic energy. This energy can be used to drive components, wheels or the like in the front of the combine harvester 2.

It should be noted that the engine 6 is controlled by a computer 160. Upon respective inputs, the computer 160 can vary the speed of the engine. By this variation also a variation of the rotational speed of shafts 118, 120, 128 and 142 can be achieved.

The basic concept of the drivetrain system shown in figure 3 is very similar, however, to increase the transmission ratio of the variable elements an intermediate shaft 140 is . integrated in the system. Whereas shafts 118, 120 are still driven from the initial drive shaft 112, the hollow wheels 128, 142 are driven indirectly from intermediate shaft 140. Variator disc 144 which transmits power from initial drive shaft 112 to inter-mediate shaft 140 variates upon activation the rotational speed of all subordinated shafts. In the embodiment shown a single alteration of the rotational speed of shaft 142 is possible by the additional variator disc 146. By this additional disc a compensation of alternations of rotational speeds caused by an activation of variator disc 144 is possible. This arrangement with an intermediate shaft 140 is also beneficial in relation to the space required for the drivetrain components. Due to the fact that variator discs always require more space than simple discs, the variator discs can be positioned elsewhere on the intermediate shaft so that the initial drive shaft 112 can be placed close to the shafts 118, 120.

Whereas a first set of variator discs 144 allows a variation of the rotational speed of intermediate shaft 140, and as a consequence of the hollow shafts 128, 142 driven by the intermediate shaft 140, there is an additional variator disc 146 to vary the rotational speed of hollow shaft 142 even further.

In figure 4, the variation of rotational speeds of the shafts 128, 142 is not achieved by variator disc, but by motors with variable speed. The power unit 106 generates electric or hydraulic energy, which is transmitted by hoses or wires 148 to the motors 150. The power from the motors is transmitted to toothed wheels 152, which are combing with the toothed wheels on hollow shafts 128, 142. The speed of the motors is variable, and the variation is transmitted upon the hollow shafts 128, 142.

The examples shown in the figures and explained above are not meant to be limited towards the embodiments shown. Of course it is possible for an expert to adapt the concepts described towards the requirements of his application, and functional elements of one example may be integrated into the concept from another example.

Claims

1. Combine harvester with at least one separation unit comprising a rotary drivensepara- tion rotor arranged in a rotor housing with a feeding zone where harvested material is fed into the rotor housing a separation zone with sieve means arranged in the rotor housing of said separation zone, a discharge zone which is located at the discharge end of the rotor housing and a suckingblower unit which sucks an air flow stream at least through the sieve means into the separation zone and the discharge zone, and a grain collecting element arranged in some distance towards the sieve means, all arranged such that a part of the air flow stream is sucked into the separation zone from the space between the sieve means and the grain collecting element, characterized in, that the rotational speeds of a sucking blower unit (36, 54) and the corresponding separation rotor (24, 44) are variably adjustable relative to each other by adjusting their drive means (26).

2.Combine harvester according to claim 1 , characterized in, that the shafts of a sucking blower unit (36, 54) and the corresponding separation rotor

(24, 44) are coaxially arranged, one of said shafts is made as a hollow shaft, and the other shaft is projecting through the hollow shaft.

3.Combine harvester according to clam 1 or 2, characterized in, that the rotational speed of at least a sucking blower unit (36, 54) is variably adjustable.

4. Combine harvester according to one or more of the preceding claims, characterized in, that the rotational speed of either the sucking blower unit or the separation rotor is adjustable by varying, the working speed of the engine.

5. Combine harvester according to one or more of the preceding claims, characterized in, that there is a first separation unit connected with a second separation unit for cleaning the grain fraction separated in the first separation unit, the shafts of the separation ro- tors and the sucking blower units of both separation units are driven from one initial driving shaft with at least three discs being fixed on said initial driving shaft, at least one of said three discs being a variator disc.

6. Combine harvester according to one or more of the preceding claims, characterized in, that besides an initial driving shaft there is an intermediate shaft with at least one variator disc fixed on it.

7.Combine harvester according to one or more of the preceding claims, characterized in, that the shaft of a separation rotor (24, 44) projects through the full length of its rotor housing and at its front end there are means (52) to transmit power for operating other working elements of the combine harvester (2).

8. Combine harvester according to one or more of the preceding claims, characterized in, that at least one shaft of a separation rotor or a sucking blower unit is driven by a hydraulic or electric motor with a variable driving speed.