GB2195223A

GB2195223A - Sorting apparatus for potatoes

Info

Publication number: GB2195223A
Application number: GB08716857A
Authority: GB
Inventors: Morgan J Milne
Original assignee: MILTEC AGRICULTURAL Ltd
Current assignee: MILTEC AGRICULTURAL Ltd
Priority date: 1986-07-17
Filing date: 1987-07-17
Publication date: 1988-04-07
Anticipated expiration: 2007-07-17
Also published as: GB8617515D0; GB2195223B; GB8716857D0

Abstract

A potato sorting apparatus is described in which means are provided for changing the direction of flow of potatoes associated with a conveyor so that the potatoes are moved across the field of vision of the sorter. In particular, this is provided by using a plurality of rollers (16) of sequentially shorter lengths which are in line with the first conveyor (14) so that the potatoes drop onto a cross-conveyor substantially at right angles to the first conveyor (14) and series of sequentially driven rollers. This has the effect of providing very even distribution of the product across a transverse conveyor (18) allowing immediate and complete access to the product for inspection and sorting. <IMAGE>

Description

SPECIFICATION Potato sorting apparatus The present invention relates to potato sorting apparatus particularly, but not exclusively, for use with mobile harvesting vehicles.

Potato harvesters lift the crop out of the ground by sliding the surrounding soil onto a moving slated belt, generally known as "the continental web", which is generally agitated to remove most of the soil as the crop progresses along the inclined surface. Devices can be incorporated to remove the residue of potato haulm. The remaining potato tubers plus clods, stone etc. pass through the rest of the harvester and are either temporarily stored in a bunker on the machine or, more typically, elevated directly into trailers running alongside the harvesters. Generally, potato harvesters are imported from countries where soils are relatively stone free and simple flow through unmanned machines are used. In the United Kingdom there tends to be a considerable amount of stones and other material in the soils and facilities must be provided for manual inspection and sorting on the harvester.

The provision of such sorting facilities must be commensurate with the even flow of the product and minimise tuber damage whilst maximising the ergonomic aspects of manual sorting.

Harvesters with sorting facilities generally fall into two classes; those with a straight ahead picking table and those with a crossways picking table.

To go onto the straight ahead picking table type a lifting width of approximately 60 inches on a two-row harvester is maintained through the soil separation sections and on to a similar width plain belt moving towards the pickers. With this structure, evenness of product flow is maintained but the ergoncmics of picking extraneous material from a belt moving towards one's hand is impractical. Sorting in this manner is tiring and generally ineffective.

With regard to the cross-ways picking table, ergonomically this is generally the most desirable way for manual sorting of the product.

Howver, it has been found that difficulty can arise in maintaining evenness of product distribution without increasing linear distances of tuber travel by the provision of additional conveyors and transfer points, with attendant potential for tuber damage.

Accordingly, a potato sorting device should satisfy a number of desirable features in addition to being relatively inexpensive and easy to use. It should permit efficient and easy sorting of potatoes without comprimising evenness of distribution. It should also optimise ergonomic aspects of manual sorting by passing the product laterally across the sorter's field of vision. It should minimise the risk of damage to individual tubers and should utilise space efficiently to permit smaller machines to be used without prejudicing performance.

An object of the present invention is to obviate or mitigate disadvantages associated with aforementioned devices.

This is achieved by providing means for changing the direction of flow of potatoes associated with a conveyor so that the potatoes are moved across the field of vision of the sorter. In particular, this is provided by using a plurality of rollers of sequentially shorter lengths which are in line with the first conveyor so that the potatoes drop onto a crossconveyor substantially at right angles to the first conveyor and series of sequentially driven rollers. This has the effect of providing very even distribution of the product across a transverse conveyor allowing immediate and complete access to the product for inspection and sorting.

The series of sequentially driven rollers can be achieved by other designs such as using small narrower conveyors of varying lengths or by using a full width conical roller. The sorting table is disposed at 90" to the stub rollers although it will be appreciated that any other suitable transverse angle could be used.

Accordingly, in one aspect of the present invention there is provided object sorting apparatus for use with a conveyor system comprising a first web for transporting unsorted objects, a second sorting web for transferring objects for sorting disposed transversely to said first web, object distribution means disposed in alignment with said first web and above said second sorting web for transferring objects from said first to said second web and for providing evenness of distribution of objects landing on said sorting web to facilitate sorting thereof.

Preferably said objects to be sorted are potatoes.

Preferably also, said object distribution means are a plurality of rollers of sequentially shorter length. Alternatively said object distribution means is provided by a conical roller or by a series of smaller narrower conveyors of varying lengths.

Preferably also, said potato distribution means is an associated drag mechanism for driving said distribution means to move said objects in the same direction as said first conveyor.

Preferably also, said potato sorting apparatus is combined with a potato harvester to provide a complete potato harvesting and sorting device.

These and other aspects of the invention will become apparent from the following description when taken in combination with the accompanying drawings in which: Fig. 1 is a perspective view of a potato harvester including a potato sorting device in accordance with an embodiment of the pre sent invention; Fig. 2 is an enlarged diagrammatic view of an embodiment of the potato sorting device illustrated in Fig. 1, and Fig. 3 is an enlarged view of the roller drive assembly.

Reference is first made to Fig. 1 of the drawings which illustrates a potato harvester which has a plurality of rotary discs and drums for guiding up soil so that potatoes can be fed onto a first conveyor 12 which directs the potatoes onto a conveyor 14 which has a plurality of sequentially shorter stub rollers generally indicated by reference numeral 16 aligned therewith. A cross-conveyor indicated by reference numeral 18 is disposed at a right angle to the conveyor 14 and stub rollers 16 and also at a lower level. As the conveyor 14 conveys potatoes onto the stub rollers 16 the products drop off the rollers and land on the conveyor 18 moving at right angles to the initial direction of travel. This has the effect of giving a very even distribution of the product across the conveyor 18.Sorting platform 20 is provided parallel to conveyor 18 and permits immediate and complete access to the product on the conveyor 18 for inspection and sorting.

The sorted potatoes are carried by a cart elevator to a storage bin, not shown in the interests of clarity, disposed at the rear of the harvester.

It will be appreciated that different conveyor and cart elevator arrangement can be provided depending on the type of harvester. With this arrangement the potatoes for sorting pass across the operators field of view in an even manner and facilitate efficient and rapid sorting and optimises the ergonomic aspect of the manual sorting. There is minimal risk to the damage of individual tubers and limited space at the top of the harvester is utilised efficiently. Accordingly this principle can be applied to small harvesters.

The structure can be best seen as illustrated in Fig. 2 of the drawings in which potatoes to be sorted travel along the conveyor 14 onto a plurality of sequentially shorter stub rollers 16.

The stub rollers 16 rotate in the same direction as the -conveyor 14. Disposed beneath the stub rollers is a conveyor 18 which is orientated at 90" to the conveyor 14. As the potatoes travel from the conveyor 14 onto the stub rollers 16 the stub rollers cause the potatoes to be evenly distributed on conveyor 18 so that a sorting platform 20 disposed parallel to conveyor 1 8 permits sorters to rapidly and efficiently inspect the potatoes on the conveyor 18 and to remove any foreign objects so that efficiently sorted potatoes are carried by the cart elevator 22 to a storage bin at the side or the rear of the harvester.

Various modifications can be made to the structure hereinbefore described without departing from the scope of the invention, for example, the plurality of sequentially shorter rollers can be replaced by a plurality of conveyors of narrower widths or different lengths to achieve a similar effect or it can be replaced by a single full width conical roller.

The plurality of rollers, the conveyors and the full width conical rollers are driven by an assembly best seen in Fig. 3. The stub rollers 16 are mounted on roller support bearings 30 coupled to side frame 32. Roller drive shafts 34 have paired drive and driven sprockets 36 mounted thereon. The drive sprockets are alternately connected from one shaft to the next by lengths of chain 38. This has the effect of driving all rollers with similar direction and speed to achieve desired product flow and additionally allows the option of driving each roller sequentially faster eliminating any possibility of small stones becoming trapped between the contra-moving surfaces of two adjacent rollers. It will be appreciated that the rollers must be driven so that product flows in the same direction as that on conveyor 14.

Advantages of the invention are that a change in direction of flow causes an evenness of product distribution in the new direction and the use of the series of shorter rollers, or of any equivalent alternative arrangement, provides even product distribution and optimises the ergonomic aspects of manual sorting by passing the product laterally across the field of vision. The structure minimises the risk of damage to individual tubers and available space on the harvester is utilised efficiently and the design principle is applicable to machines of varying size.

Claims

1. Object sorting apparatus for use with a conveyor system comprising a first web for transporting unsorted objects, a second sorting web for transferring objects for sorting disposed transversely to said first web, object distribution means disposed in alignment with said first web and above said second sorting web for transferring objects from said first to said second web and for providing evenness of distribution of objects landing on said sorting web to facilitate sorting thereof.

2. Apparatus as claimed in claim 1 wherein said objects to be sorted are potatoes.

3. Apparatus as claimed in claim 1 or 2 wherein said object distribution means are a plurality of rollers of sequentially shorter length.

4. Apparatus as claimed in any preceding claim wherein said object distribution means is provided by a conical roller or by a series of smaller narrower conveyors of varying lengths.

5. Apparatus as claimed in any preceding claim wherein said potato distribution means is an associated drag mechanism for driving said distribution means to move said objects in the same direction as said first conveyor.

6. Apparatus as claimed in any preceding claim wherein said potato sorting apparatus is combined with a potato harvester to provide a complete potato harvesting and sorting device.

7. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.