GB2224423A

GB2224423A - Grain collecting and cleaning apparatus in a combine harvester

Info

Publication number: GB2224423A
Application number: GB8923720A
Authority: GB
Inventors: Karl-Heinz Radke; Klaus Eckert; Volker Windisch; Mattias Strassberger; Jan-Diego Geissler
Original assignee: VEB Kombinat Fortschritt Landmaschinen Neustadt (Bestand)
Current assignee: VEB Kombinat Fortschritt Landmaschinen Neustadt (Bestand)
Priority date: 1988-11-04
Filing date: 1989-10-20
Publication date: 1990-05-09
Anticipated expiration: 2009-10-20
Also published as: GB8923720D0; BE1004590A3; RU1837740C; FR2638603B1; FR2638603A1; DD276616A1; GB2224423B; DE3932945A1

Description

2224423 GRAIN COLLECTING AND CLEANING APPARATUS IN A COMBINE HARVESTER The

present invention relates to a combine harvester provided with a grain cleaning and collecting apparatus.

Cleaning equipment with associated grain-collecting and conveying equipment in combine harvesters are known in different constructions. Thus, for example, a combine harvester is illustrated in the Fig. 1 of DDPS 149 451 in which an upper sieve device consists of three individual sieve elements arranged one displaced relative to the other in different planes with intermediate drop steps flowed through by air.

A lower sieve element extends continuously over the entire length of the individual upper sieve elements so that the entire harvest stock sieved at the upper sieve elements passes to the lower sieve element. Since a large part of the cleaned grain is already separated at the front upper sieve element, this grain proportion loads the lower sieve element and reduces its performance capability.

A three-stage cascade cleaning equipment with three adjustable sieves, which partially overlap, is disclosed in FR-PS 1 531 947. All sieve surfaces and droo steps between the sieves are acted on by an air current. The air current i.s orovided by a blower which has only one outflow channel. Since only a low air speed is present in the region between the drop steD between a stepped base of threshing equipment and the first sieve, the stock falling onto the first sieve is correspondingly subject to only a reduced throughflow, so that chaff and short straw components are only in part blown across the sieves out of the -combine harvester. A large part of the impurities therefore falls together with the separated grains through the first sieve into the grain worm disposed thereunder, whereby the degree of purity of the cleaned stock is reduced.

1 1 In cleaning equipment for a combine harvester disclosed in DEOS 30 42 733, a preliminary cleaning sieve, which lies below the delivery region of a stepped base of threshing equipment, is arranged between the stepped base and the upper sieve. A cleaning air current is directed, through an additional outflow channel of the blower, onto the stock passing the drop step and below the preliminary cleaning sieve. A step-shaped collecting base is arranged underneath the preliminary cleaning sieve. At the delivery end of the collecting base, the stock falls onto the lower sieve disposed thereunder. The stepped 10, base, the preliminary cleaning sieve, the collecting base and the upper sieve are oscillatingly driven in synchronism. A disadvantage of this cleaning equipment is that the grain, which has been separated at the preliminary cleaning sieve and already has a high degree of purity, reaches the lower sieve and there is mixed with stock mixture falling from the upper sieve. In this construction, the lower sieve and the grain conveyor worm are loaded with the entire sieved stock separated at the cleaning equipment, whereby the degree of purity of the grain or the throughput performance is reduced.

There is therefore a need to increase the performance capability of the cleaning equipment, in particular by so constructingand arranging a grain conveying system within cleaning equipment that a lower sieve may be relieved and the degree of purity of the grain and throughput performance may be increased thereby.

According to the present invention there is provided a combine harvester provided with grain cleaning and collecting apparatus comprising a plurality of upper sieve elements disposed at a spacing below a threshing equipment base to receive grain, chaff and straw 1 1 mixture therefrom and arranged vertically spaced relative to each other in respective planes with a drop from one element to the next, a lower sieve element disposed below the upper sieve elements, blowing means comprising a blower, lower duct means to direct air from the blower towards the lower sieve element and upper duct means to direct air from the blower towards a forward and uppermost one of the upper sieve elements and the space between that element and the threshing base, a grain collecting trough disposed below and extending over substantially the entire area of said one of the upper sieve elements, a conveyor arranged at the base of the trough to convey collected grain out of the trough, and grain transport means to transport grain from the trough to storage means.

In a preferred embodiment, a mixture of grain, chaff and short straw conveyed by threshing equipment onto a stepped base is conducted to the cleaning and collecting apparatus, which comprises a blower with a main outflow channel and an additional channel and upper sieve elements and a lower sieve element, with associated grain-collecting and conveying means for further grain separation. The upper sieve elements are arranged one displaced from the other in different planes with drop steps lying therebetween. The entire region of a front one of the upper sieve elements, inclusive of the associated drop step between the stepped base and that element, is loadable by an air current from the additional channel of the blower. The collecting trough is arranged underneath the front upper sieve element and extends over its entire area. A conveyor worm is arranged at the base of the trough and this worm is disposed in conveying connection, by way of a collecting worm, with a grain elevator and a grain tank.

1 Preferably, the end region of the upper channel wall of the main outflow channel of the.blower is formed by the base of the collecting trough. The grain quantities separated off at the lower sieve element and at the front upper sieve element are conveyed separately by way of the grain-collecting and conveying arrangements as far as the collecting worm and thereafter together by way of the grain elevator to the grain tank. The grain separated off at the lower sieve element is conducted to the collecting worm by way of an elevator conveyor arranged laterally beside the harvester frame and extending obliquely upwards.

The delivery opening of the elevator conveyor is arranged above the receiving region of the collecting worm. 'The-final cleaning equipment, with a collector housing mounted thereunder for the separated grains, is arranged above the elevator conveyor, wherein the collector housing is connected with the elevator conveyor and the separated grains are conducted by way of the collecting worm and the grain elevator to the grain tank.

By means of apparatus embodying the invention, a substantial separation of the grain from foreign bodies "in the harvested stock, and separate removal of the cleaned grain into the grain tank, take place in the region of the front upper sieve element without it being necess- ary to run through all cleaning stages once again. As a result, the cleaning assemblies arranged downstream and, in particular, the lower sieve element are relieved to a substantial extent, so that the degree of purity of the grain and the throughput performance are increased.

An embodiment of the present invention will now be more particular ly described by way of example with reference to the accompanying drawings, in which:

1 1 Fi g. 1 Fi 9. 2 Fi 9. 3 Fi g. 4 Fi 9. 5 is a partly sectional side elevation of an axial flow combine harvester embodying the invention; is a longitudinal sectional view of grain cleaning and collecting apparatus of the harvester; is a plan view of the apparatus; is a section along the line A-A in Fig. 3; and is a section along the line B-B in Fig. 3.

Referring now to the drawings, there is shown in Fig. 1 an axial flow combine harvester 1 in which harvested stock passes from a cutting mechanism by way of an intake channel 2 to a threshing and separating drum 3. In the course of the conveying movement, threshing of the stock takes place between a threshing basket 5 and threshing strips 4 disposed in helical arrangement at the circumference of the drum 3.

In a straw delivery region 6, straw is discharged onto the field through laterally mounted straw guide channels as a result of the centrifugal forces at the drum 3. The mixture of grain, chaff and short straw separated out at the basket 5 passes to a stepped base 7 disposed thereunder. On this, there takes place a conveying movement, loosening and stratification of the stock mixture in direction towards cleaning and collecting apparatus. The apparatus comprises a blower 8, a lower sieve element 9 and an upper sieve device which consists of three individual upper sieve elements 10, 11 and 12, which are arranged displaced relative to each other in different planes with respective drop steps 13 and 14, flowed through by air current from the blower 8, disposed therebetween. Guide grates 15 are mounted at the ends of the sieve elements 10, 11 and 12.

The blower 8 has a main outflow channel 16 and an additional channel 17. Outflow openings of the channel 17 are so arranged that the drop step 18 between the base 7 and the front upper sieve element 10 as well as the region below and behind the element 10 are subjected to an air current. The light stock components are blown away over the front sieve element 10 by this directed current, whilst the separated grains fall into a collecting trough 19 arranged underneath the element 10. The end region of an upper wall 20 of the channel 16 is formed by the base of the trough 19.

A conveying worm 21 is mounted in transverse direction at the base of the trough 19. The grains conveyed therein reach a collecting worm 22, which feeds a grain elevator 23. The grains are conveyed by way of the elevator 23 into a grain tank 24.

The middle and rear upper sieve elements 11 and 12 are acted on by an air current from channel 16 of the blower 8. The air quantity distribution between the channels 16 and 17 is controlled by an adjustable flap 25. The direction of the air current to the middle and rear upper sieve elements 11 and 12 as well as to the lower sieve element 9 is adjusted by means of a further flao 26 arranged in the end region of the channel 16. All light components are separated out from the stock mixture and carried out rearwardly of the harvester due to the controllable air flow to the sieves and drop steps. The grains separated out at the elements 11 and 12 and other admixtures pass to the lower sieve element 9 and are there subjected to a repeated sieving.operation. Since the lower sieve element 9 is relieved to a substantial extent in consequence of the separated grain removal in the region of the sieve element 10, the effectiveness of the grain separation at the sieve element 9 is increased.

1 1 1 1 - 7 1 The separated grains fall from the lower sieve element 9 onto a grain base 27, which extends obliquely and at the lower end of which a grain worm 28 is arranged. The worm 28 conveys the grains to an elevator conveyor 29 mounted laterally beside the machine frame. The conveyor 29 extends obliquely towards and ends above the collecting worm 22. The grains transferred from the delivery opening of the conveyor 29 to the worm 22 are delivered to the tank 24 by the elevator 23. The stock mixture, which has been separated in the end region of the rear upper sieve element 12 and the lower sieve element 9 and con- sists predominantly of grain and short straw components, passes by way of a return base 30 to a transverse conveyor worm 31, which conveys the stock mixture into a mixture elevator 32. This transfers the stock mixture to further cleaning equipment 33, which is arranged above the conveyor 29. The grain separated out in the equipment 33 passes by way of a collector housing 34 directly into the conveyor 29 and by way of the worm 22 and the elevator 23 into the tank 24. Separated out foreign bodies are discharged directly from the equipment 33 onto the field.

Claims

- 8 CLAIMS 1. A combine harvester provided with grain cleaning and

collecting apparatus comprising a-plurality of upper sieve elements disposed at a spacing below a threshing equipment base to receive grain, chaff and straw mixture therefrom and arranged vertically spaced relative to each other in respective planes with a drop from one element to the next, a lower sieve element disposed below the upper sieve elements, blowing means comprising a blower, lower duct means to direct air from the blower towards the lower sieve element and upper duct means to direct air from the blower towards a forward and uppermost one of the upper sieve elements and the space between that element and the threshing base, a grain collecting trough disposed below and extending over substantially the entire area of said one of the upper size elements, a conveyor arranged at the base of the trough to convey collected grain out of the trough, and grain transport means to transport grain from the trough to storage means.
2. A harvester as claimed in claim 1, wherein a base portion of the trough defines an upper wall portion of the upper duct means at an air outlet end region thereof.
3. A harvester as claimed in either claim 1 or claim 2, the transport means comprising a collecting worm conveyor and an elevating conveyor.
4. A harvester as claimed in claim 3, comprising respective grain collecting and conveying means to collect grain from the lower sieve element and to convey the collected grain to the worm conveyor of the transport means.

i% i i
5. A harvester as claimed in claim 4, said grain collecting and conveying means comprising a-respective elevating conveyor arranged at a side of the apparatus and extending obliquely upwards to the worm conveyor of the transport means.
6. A harvester as claimed in claim 5, wherein the elevating conveyor of said grain collecting and conveying means has a discharge portion arranged above an inlet region of the worm conveyor.
7. A harvester as claimed in either claim 5 or claim 6, comprising additional grain cleaning means arranged above the elevating conveyor of said grain collecting and conveying means, and a grain collector housing disposed below the cleaning means and arranged to conduct collected grain to the elevating conveyor.
8. A harvester provided with grain cleaning and collecting aoparatus substantially as hereinbefore described with reference to the accompanying drawings.

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