GB2145612A - A device for separating clod and-or stones from root vegetables or bulbs - Google Patents

Abstract

The device comprises two spaced parallel contrarotatable members (31, 32) one of which (32) is in the form of a roller having a rigid outer surface and the other of which (31) has a plurality of radially outwardly extending resiliently deformable projections (40). The device may have at least one further rotatable member (30). The clod and/or stones fall between the members (30 and 31) and between the member (31) and roller (32) whilst root vegetables or bulbs pass thereover. The device will normally be installed on a harvester downstream of the final open web of the harvester. <IMAGE>

Description

SPECIFICATION A device for separating clod and/or stones from root vegetables or bulbs This invention relates to a device for separating clod and/or stones from root vegetables or bulbs, particularly but not exclusively for use on a harvester, for example a potato harvester.

It is known to provide a clod separator on a potato harvester. This known separator comprises a contra-rotating roller mounted in a spring loaded holder at the discharge end of a conveying web. The contra-rotating roller co-operates with the web to remove clod, but it has the disadvantage that stones will either cause the clod roller to jam or will move the clod roller against its spring loading away from the web and this has the effect of allowing potatoes to also pass between the web and clod roller. These potatoes are then lost resulting in a reduced crop yield. Moreover, due to the rigidity df the web and roller and the hardness of the stone the consequential damage to the harvester is very high.

In its broadest aspect, the invention provides a device for separating clod and/or stones from root vegetables or bulbs, comprising two rotatable members one of which has a resilientiy deformable part or parts, the rotatable members being mounted for rotation in opposite angular directions about parallel spaced axes, and being constructed and arranged such that in use clod and/stones is drawn down between the two rotatable members while the root vegetables or bulbs pass thereover.

In a preferred aspect, the invention provides a device for separating clod and/or stones from root vegetables or bulbs, comprising two rotatable members mounted for rotation in opposite angular directions about parallel spaced axes, one of the rotatable members being in the form of a roller and the other having a plurality of radially outwardly extending resiliently deformable projections, the arrangement being such that in use clod and/or stones is drawn down between the two rotatable members whilst root vegetables or bulbs pass thereover.

Preferred and/or optional features of the preferred aspect of the invention are set forth in claims 3--13.

The invention also provides a root vegetable or bulb harvester having a device according to either of the aforementioned aspects of the invention The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic side view of a known unmanned potato harvester on which a device embodying the invention may be installed.

Figure 2 is a simplified perspective view of one embodiment of a device according to the invention, with many of the parts omitted for reasons of clarity; Figure 3 is a section taken through the device of Figure 2 in a plane normal to the axes of the rotatable members.

Referring firstly to Figure 1,the potato harvester shown therein comprises disc coulters 10, two twin bladed digging shares 11, diablo rollers 12 shaped to run on the ridge tops to maintain the depth of digging shares 11, and first and second open webs 13 and 14 respectively. The harvester is coupled to a tractor draw bar (not shown) attached to the forward or right hand end (as shown in Figure 1) of the harvester and drive for the moving parts of the harvester is taken from the power take-off shaft of the tractor. The harvester could, however, be selfpropelled. The web 13 is guided over non driven rollers 15 and driven rollers 16 and 17. The web 14 is guided over non driven rollers 18 and drive roller 19.

The web 13 has an adjustable rocker type agitator 20 and an optional adjustable rotating agitator 21. The web 14 has an adjustable rotating agitator 22. The agitators 20,21 and 22 are used to help sift loose or friable soil through the respective web 13, 14. Each web 13, 14 has an adjustable contra-rotating haulm roller 23, 24 respectively at the discharge end of the respective web. These haulm rollers 23, 24 are designed to grip and extract haulm and weed.

Above each haulm roller 23,24 is a set of weighted fingers 25, 26 respectively to help guide the haulm and weeds down into the haulm rollers. A finger bar oscillator (not shown) may be fitted across the first open web 13 to spread haulm and weed and thereby present a more uniform flow to the haulm roller 23.

Such a harvester is well known in the art and a more detailed description is therefore considered to be unnecessary.

In such a known harvester potatoes, clod and stones discharged from the second open web 14 would normally be delivered to an elevator (not shown), which extends at right angles to the direction of movement of the webs 13 and 14, by a further web which is downwardly inclined. The potatoes, clod and stone are delivered by the elevator into a trailer drawn by a furthertractor and the clod and stones and any other unwanted material is subsequently separated from the potatoes by equipment installed in a barn.

Referring now to Figures 2 and 3, the separating device shown therein can be installed on the harvester in place of the aforementioned further web. The separating device comprises three driven rotatable members 30,31 and 32. The rotatable members 30 and 31 each comprise a plurality of axially spaced star wheels 33,34 and rotate in the same angular direction as drive roller 19 for the second open web 14. The rotatable member 32 is in the form of a clod roller having a rigid outer surface and rotates in an opposite angular direction to rotatable members 30 and 31. The three rotatable members 30, 31 and 32 have their axes arranged in spaced relationship. The axes of members 30 and 31 are in a common horizontal or substantially horizontal plane below the axis of the haulm roller 24 and the axis of the roller 32 is below that of the axes of the members 30 and 31.The three rotatable members 30,31 and 32 are mounted in a common support 35 which can be readily attached to the harvester so that existing harvesters can be modified. The axes of the rotatable members 30 and 31 are fixed relative to one another but the rotatable member 32 is carried at opposite ends by spring loaded swing arms 36 (see Figure 3) which enable the rotatable member 32 to move away from the rotatable member 31 in the event that a large stone, which would otherwise jam the separating device, gets between the rotatable members 31 and 32. The clod roller 32 has an associated cleaning blade 41.

The star wheels 33,34 of the rotatable members 30,31 are keyed to respective driven shafts 37,38 and are spaced apart by sleeve-like spacers 39. The star wheels are of resiliently deformable material, preferably an elastomeric material, and each has a plurality of radially outwardly extending equiangularly spaced fingers 40. The leading edge of each finger 40 is preferably but not necessarily convex and conveniently the trailing edge of each finger is concave. In the preferred embodiment the star wheels on one of the rotatable members 30 and 31 each have for example 6 fingers whilst the star wheels on the other of the rotatable members 30 and 31 each have for example 12 fingers and the rotatable members 30 and 31 are interchangeable for a purpose to be described later. However, the star wheels on the two rotatable members 30 and 31 could have the same number of fingers.

The star wheels 33 on the rotatable member 30 are axially staggered with respect to the star wheels 34 on the rotatable member 31 so that during rotation the fingers 40 of the star wheels 33 pass between the fingers of the star wheels 34. The space between axially adjacent star wheels is preferably only slightly greater than the width of the fingers 40 and the rotatable members 30 and 31 are spaced apart such that when undeformed the tips of the fingers of the star wheels on one of the rotatable members 30 and 31 come into close proximity with but do not actually contact spacers 39 of the other of the rotatable members 30 and 31. This has the advantage that the star wheels 33 and 34 will be self cleaning.

When the clod roller 32 is in its normal position (i.e. in a position in which it is not urged away from rotatable member 31 against its spring loading) the rotatable member 31 and clod roller 32 are spaced apart such that when undeformedthetips of the fingers 40 of the star wheels on the rotatable member 31 come into close proximity with but do not actually contact the peripheral surface of the roller 32.

In operation potatoes, clod and stones are discharged from the second open web 14 of the harvester onto the separating device, the haulm roller 24 having first taken out most if not all of the haulm and weeds not taken out by the haulm roller 23. The star wheels 33,34 of the rotatable members 30,31 serve to loosen the clod and small pieces of clod are indeed wound therebetween. The potatoes, remaining clod and stones are then fed to the clod roller 32 and owing to the resilient deformability of the fingers 40 most of the remaining clod and smaller stones are drawn between the contrarotating rotatable member 31 and clod roller 32 without any movement of the clod roller 32 against its spring loading.The potatoes and any clod or stones not removed by the separating device will then be fed to the elevator of the harvester either directly or via one or more downwardly inclined webs or a further similar separating device series mounted with the separating device described above.

Whilst it is inevitable that some clod and stones will escape extraction by the clod separator it is thought that with the aforesaid arrangement the potatoes reaching the elevator will be as much as 95% clean as compared with potatoes which are often only about 75% clean in known unmanned harvesters.

Also it is inevitable that there will be some loss of crop yield as the clod roller 32 will move against its spring loading to allow the passage of some larger stones between the clod roller 32 and rotatable member 31 but this loss of yield is expected to be insignificant.

The separating device does not necessarily have to have both rotatable members 30 and 31 but the advantage of having the two or indeed more than two is that they give the clod and potatoes time to settle down before they reach the clod roller 32; thereby reducing the risk of clod and potatoes bouncing over the clod roller 32. Moreover, the provision of two interchangeable rotatable members 30 and 31 each having star wheels with a different number of fingers is advantageous in that when harvesting early potatoes the rotatable member with the larger number of fingers can be arranged next to the clod roller 32 to minimise loss of crop yield and when harvesting late potatoes the rotatable member with the smaller number of fingers can be arranged next to the clod roller 33 to obtain efficient clod removal.

If one or both rotatable members 30 and 31 are provided with star wheels with a relatively small number of fingers, e.g. six, the fingers of each pair of adjacent star wheels of the respective members 30,31 are arranged to angularly bissect one another when viewed along the axis of the respective member, as shown in Figure 3, in order to minimise the risk of potatoes being drawn down between members 30 and 31.

The aforementioned separating device may be used with harvesters adapted to harvest other root vegetables such as onions, carrots, swede, turnip and red beet but not sugar beet, or bulbs such as daffodil ortulip bulbs. It could also be used with in store equipment rather than on a harvester.

The invention is not limited to the specific embodiment described but is limited only by the appended claims. For example, instead of the star wheels with fingers the rotatable member(s) 30,31 could have other appropriate radially outwardly extending resiliently deformable projections.

Moreover, other configurations and/or arrangements of contra-rotating rotatable members could be used provided that at least one of them is deformable and provided that they serve to draw clod down between them whilst root vegetables or bulbs pass thereover.

Claims (17)

1. A device for separating clod and/or stones from root vegetables or bulbs, comprising two rotatable members one of which has a resiliently deformable part or parts, the rotatable members being mounted for rotation in opposite angular directions about parallel spaced axes, and being constructed and arranged such that in use clod and/or stones is drawn down between the two rotatable members while the root vegetables or bulbs pass thereover.

2. A device for separating clod and/or stones from root vegetables or bulbs, comprising two rotatable members mounted for rotation in opposite angular directions about parallel spaced axes, one of the rotatable members being in the form of a roller and the other having a plurality of radially outwardly extending resiliently deformable projections, the arrangement being such that in use clod and/or stones is drawn down between the two rotatable members whilst root vegetables or bulbs pass thereover.

3. The device of claim 2, wherein the spacing between the two rotatable members is such that during rotation thereof the projections of the other rotatable member come into close proximity with but do not contact the peripheral surface of the one rotatable member.

4. The device of claim 2 or claim 3, wherein the projections are in the form of radially outwardly extending resiliently deformable fingers both axially and angularly spaced apart on the other rotatable member.

5. The device of claim 4, wherein the other rotatable member comprises a plurality of axially spaced wheels, each of which has a plurality of angularly spaced radially outwardly extending resiliently deformable fingers.

6. The device of claim 4 or claim 5, wherein the leading edges of the fingers are convex.

7. The clod separator of claim 6, wherein the trailing edges of the fingers are concave.

8. The device of any one of claims 2-7, wherein the one rotatable member is a rollerwith a rigid outer surface.

9. The device of any one pf claims 2-8, wherein the one rotatable member is arranged to be downstream of the other rotatable member in relation to the direction of movement of clod and/or stones and root vegetables or bulbs thereto.

10. The device of claim 9, wherein the one rotatable member is spring-loaded in such a way that it can move away from the other rotatable member against its spring loading in order to prevent stones jamming between the two rotatable members.

11. The device of claim 9 or claim 10 when dependent on claim 5, comprising at least one further rotatable member arranged on the side of the other rotatable member remote from the one rotatable member and arranged to rotate in the same angular direction as the other rotatable member, the further rotatable member comprising a plurality of axially spaced wheels, each of which has a plurality of angularly spaced radially outwardly extending resiliently deformable fingers, the wheels of the further rotatable member being axially staggered with respect to the wheels of the other rotatable member so that in use the fingers of the further rotatable member pass between the fingers of the other rotatable member.

12. The device of claim 11, wherein the leading edges of the fingers of the further rotatable member are convex.

13. The device of claim 11 or claim 12, wherein the trailing edges of the fingers of the further rotatable member are concave.

14. The device of any one of claims 11-13, wherein the number of fingers on each star wheel of said other rotatable member is different from the number of fingers on each wheel of said further rotatable member, and said other rotatable member and said further rotatable member are interchangeable.

15. A device for separating clod and/or stones from root vegetables or bulbs, substantially as hereinbefore described with reference to and as shown in Figures 2 and 3 of the accompanying drawings.

16. A root vegetable or bulb harvester having a device according to any one of the preceding claims.

17. The harvester of claim 16, wherein the device is mounted downstream of the final open web of the harvester.