NZ510942A - Roller and planar sorting apparatus - Google Patents

Abstract

Sorting apparatus with a conveyor (1) and one or more driven rollers (3) having an outer surface spaced from the conveyor by a predetermined distance, each roller nearer to the conveyor as distance from the point of introduction increases. Pieces to be sorted (5) are transported along the conveyor to the rollers, which are placed at an angle to the path of travel, so that those pieces having a dimension less than the predetermined space between the rollers and the conveyor will pass through and those pieces that are too big are directed along the rollers to the side for disposal.

Description

New Zealand Paient Spedficaiion for Paient Number 510942 5109 42 '^effectual Property Office of N2 0 5 APR 2002 RECEIVED No.: 510942 Date: 5 April 2001 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION "Sorting Apparatus" I, Michael Edward Menhinick, a New Zealand citizen, of 135 Victoria Road, Devonport, Auckland, New Zealand, hereby declare the invention, for which I pray that a patent may-be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: 1 FIELD OF THE INVENTION This invention relates to sorting apparatus and methods, and is directed particularly but not solely toward sorting items by size such as the thickness or minimum cross section of items.

BACKGROUND OF THE INVENTION Various types of sorting apparatus are known. Typically, apparatus for sorting particulate matter or items by size consists of a container such as a tray in which the items are provided. The container is oscillated or vibrated to shuffle larger items to one location in the tray, such as one side of the tray for example where appropriate apertures or the like act as a coarse filter to sort the items by size.

Sorting articles such as pebbles which are oval or wedge shaped can represent particular problems, often causing sorting apparatus to jam. Also, existing sorting apparatus, such as that which uses vibrating trays or the like can take a long time to sort items such as pebbles and is not always easily adjusted to sort into a large number 20 of different sizes.

US patent number 4776467 to Hayasaki discloses a conveyor belt onto to which articles to be sorted are placed and two transverse conveyers are provided and spaced apart the distance corresponding to the approximate size of the articles to be sorted 25 from the remainder of the articles. This device is complex to implement in terms of the number of conveyor belts required to be provided. Conveyor belts are prone to jamming, particularly when having articles such as pebbles placed on them for sorting. Conveyor belts can also have problems with conveyors remaining on the appropriate wheels, pulleys or other driving apparatus while using the edge of the conveyor belt.

US patent number 3784006 to Braun discloses a complex arrangement which includes a plate type sorter having a perforated surface which oscillates. A second sorter is provided in the form of rollers which rotate in opposite directions and which are spaced apart in a diverging manner so that items of a desired size will fall between the rollers 2 and those which are larger than the desired size will be thrown to one side. This apparatus is very complex and expensive to implement.

OBJECT OF THE INVENTION It is an object of the present invention to provide sorting apparatus or methods which will at least go some way toward overcoming the disadvantages associated with the prior art in a simple yet effective manner, or which will at least provide the public with a useful choice.

SUMMARY OF THE INVENTION In one aspect the invention may broadly be said to consist in sorting apparatus including a substantially planar surface and a roller having an outer surface spaced from the planar surface by a predetermined distance, and first transport means to transport the matter to be sorted along the planar surface toward the roller whereby only items which have a dimension less than the predetermined distance between the outer surface and a base plate may pass between the roller and the planar surface, and driving means to drive the roller so that items that do not have a dimension less than the predetermined distance are pushed away from the roller.

In a further aspect the invention may broadly be said to consist in a method of sorting items, method comprising the steps of directing items to be sorted in a first direction along a substantially planar surface, rotating a roller spaced from the substantially planar surface in a direction such that the surface of the roller nearest the planar surface moved in the direction opposite to the direction of movement of the items to be sorted along the planar surface, items of desired size passing between the roller and the planar surface and items which are greater than the desired size being prevented from passing by the action of the roller.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting. 3 DRAWING DESCRIPTION A preferred embodiment of the invention will now be described with reference to the following drawings by way of example only Figure 1 is a perspective view of sorting apparatus according to the present invention, and Figure 2 is a partial view in cross section through part AA' of Figure 1.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to figures 1 and 2, sorting apparatus is shown. The main body of the apparatus comprises a base plate 1 which is angled to the horizontal throughout its length.

Mounted transversely, but at an angle, across the width of the base plate is one or 15 more driven rollers 3. Each roller 3 is driven by an appropriate device such as an electric motor 2. However, it will be seen that any form of appropriate driving device may be used.

The number of rollers is dependent upon the number of different thicknesses of items 20 to be sorted.

The driven rollers are mounted so as to provide predetermined uniform "sorting" gaps 9 (figure 2) between the periphery of the roller and the surface of the base plate.

The driven rollers are driven at a slow speed of rotation such that the tangent to the roller where it is closest to the plate is pointing in a direction 10 up the plate. This rotation provides a self clearing action to prevent items becoming wedged between each roller and the plate and also provides the motive force for the sideways transferral of sorted items toward apertures 4 in the plate. The rollers have a rubber or elastomer 30 coating to both protect and also grip the items being sorted to thus improve the sorting action. 4 The items to be sorted 5 (shown as smooth oval objects such as pebbles in this example) are dropped or fed onto the top end of the sloping plate 1. As the items slide down the plate 1 under the action of gravity they are guided by appropriate barriers 8 5 and will pass under each roller provided that the thickness of the item is not greater than the predetermined gap 9. Items which do not pass underneath the rollers 6 and 7 will be diverted sideways by the combined action of the rotating roller and the transverse angle of the roller across the base plate 1. Items then sorted according to thickness can be collected by falling through outlets 4 at the lower ends of the 10 transverse rollers. Alternatively, a higher speed roller can be used to eject items at a greater speed as shown by arrow 11. Items that are thinner than the pre-set sorting gaps 9 will pass under all rollers to be collected at the lower end of the table 12. In the arrangement shown in the drawings, the thickest items will be sorted first and the thinnest items last.

It will be seen that the invention has a self-clearing action which particularly lends itself to sorting smooth and wedge shaped items such as pebbles, as is shown in figure 2. The table is angled at any appropriate angle to enable quite high sorting to be achieved. Similarly, speed rotation of each of the rollers may be adjusted to achieve 20 sufficient sorting.

It will be seen that the invention has a considerable advantage in that it is very simple and therefore an inexpensive construction is provided. In particular, the apparatus is also substantially maintenance free and can sort at very high speeds without any 25 tendency to jam. A wide variety of items may be sorted, for example rocks, stones, particulate matter, confectionery items, mechanical components etc.

Variations Although the table or plate 1 has been described as being provided at an angle in order to allow movement of the items to be sorted by gravity along the plate, it will be seen that other methods may be used. For example the angled plate may be replaced with a conveyor, and the conveyor could be disposed at an angle if desired. Furthermore, the conveyor can be driven by driving means (not shown) in a selected direction along 35 the length of the plate.

Claims (13)

WHAT WE CLAIM IS:

1. Sorting apparatus including a substantially planar surface and a roller having an outer surface spaced from the planar surface by a predetermined distance, and first 5 transport means to transport the matter to be sorted along the planar surface toward the roller whereby only items which have a dimension less than the predetermined distance between the outer surface and a base plate may pass between the roller and the planar surface, and driving means to drive the roller so that items that do not have a dimension less than the predetermined distance are 10 pushed away from the roller.

2. Sorting apparatus as claimed in claim 1, wherein the planar surface comprises surface of a conveyor, and wherein the first transport means comprises driving means to drive the conveyor. 15

3. Sorting apparatus as claimed in either claim 1 or claim 2, wherein the first transport means comprises an angle provided to the planar surface whereby the upper end of the planar surface to which items to be sorted are provided is higher in elevation than a lower end of the planar surface, the lower end being the end to which items 20 which have a dimension less than the predetermined distance size are transported.

4. Sorting apparatus as claimed in any one of the preceding claims, wherein the apparatus includes a second transport means whereby items which do not pass between the roller and the planar surface are directed toward one side or area of 25 the surface to be removed therefrom.

5. Sorting apparatus as claimed in claim 4, wherein the second transport means comprises placing the roller at an angle to the general path of travel of items by the first transport means so that matter which does not pass between the roller and the 30 planar surface travels along the roller to an aperture or side of the surface for disposal.

6. Sorting apparatus as claimed in any of the preceding claims, wherein the outer surface of the roller is part of an elastic or resilient coating on the roller. 35 6

7. Sorting apparatus as claimed in claim 6, wherein the coating on the roller comprises a rubber or elastomer.

8. Sorting apparatus as claimed in any of the preceding claims, wherein a plurality of 5 rollers are provided, each roller being provided at a distance which is nearer to the planar surface as distance from the point of introduction of the items to the planar surface is increased.

9. Sorting apparatus as claimed in any one of the preceding claims, wherein a 10 plurality of rollers are provided, each being provided at a uniform distance from the planar surface.

10. Sorting apparatus as claimed in either claim 8 or claim 9, wherein the rollers are driven at a slow speed. 15

11. A method of sorting items, method comprising the steps of directing items to be sorted in a first direction along a substantially planar surface, rotating a roller spaced from the substantially planar surface in a direction such 20 that the surface of the roller nearest the planar surface moved in the direction opposite to the direction of movement of the items to be sorted along the planar surface, items of desired size passing between the roller and the planar surface and items which are greater than the desired size being prevented from passing by the action of the roller. 25

12. Sorting apparatus substantially as herein described with reference to the accompanying drawings.

13. A method of sorting items substantially as herein described with reference to the accompanying drawings. Intel[ectual PIPER KNOWLES Attorneys for Michael Edward Menhinick °®oeVrNrrfy 0 5 Apft 2QQ2 REC EIYeq