WO2010005309A1

WO2010005309A1 - Singulator

Info

Publication number: WO2010005309A1
Application number: PCT/NL2009/050416
Authority: WO
Inventors: Albertus Johannes Ruigrok
Original assignee: FPS Food Processing Systems BV
Current assignee: FPS Food Processing Systems BV
Priority date: 2008-07-10
Filing date: 2009-07-10
Publication date: 2010-01-14
Anticipated expiration: 2011-01-10

Abstract

Apparatus for singulating in particular unround products (P), such as fruits, eggs or tubers, comprising: an endless conveyor, which conveyor (1) is provided with at least one row, extending in the transport direction (T), of carriers configured such that between each two successive carriers in the row a transport position for a product (P) is formed, with each carrier comprising two rollers (4a, 4b), of which a first (4) is arranged on a first pivot (5a) and a second (4b) on a second pivot (5b)^, wherein the first and the second pivot (5a, 5b) each include a substantially equal acute angle (alpha, beta) with a vertical plane (Vl) extending through the middle of the row of carriers in the transport direction (T) and wherein the two pivots (5a, 5b) each extend slightly obliquely upwards from that plane, with the sum of the acute angles being less than 180°; and provided with a drive unit (8) for rotating the rollers (4a, 4b) of the carriers.

Description

Title: Singulator

The present invention relates to an apparatus for singulating products, for instance vegetables, fruit, or eggs, more particularly unround products such as, for instance, pears or sweet peppers.

Such a singulator is known for instance from NL1010417. In that patent specification, it is described how products supplied in bulk are dumped onto rows composed of successive driven diabolo-shaped rollers. Such a row of rollers constitutes an endless conveyor. More particularly, each roller consists of two halves in the shape of substantially a truncated cone, with centrally therebetween a further constriction, namely cylinder - shaped, provided around the pivot around which these rollers can be rotated. With this substantially diabolo-shaped relief, the intention is for the products, for instance apples or sweet peppers, which are randomly dumped onto these rollers, to be ordered one after the other, referred to as singulating, so that between each two successive rollers a transport position is formed where a single product sits and is carried along. The further constriction referred to is employed to afford free space to any stalks or residues thereof to thereby enable a more uniform rotation rather than unpredictable bouncing as a result of irregular push against and resilience of such a stalk. In FR2682941 a further example of such a singulator is described. In that patent specification, also diabolo-shaped rollers are used, with each row of rollers situated in a gutter whose walls are formed by brush elements. The bristles of the brush elements are oriented in the direction of the constricted portion and just touch the edges of the oblique diabolo surfaces. This is intended to slow down any stacked and non-singulated products through friction with the bristles and cause them to take up a free position located further upstream. The friction with these bristles is such that damage of products is avoided. For the above-described situations, the following properties of such rollers are combined:

- the constricted portion in the middle prevents products falling off the rollers over the edges as a result of rotation, allowing them instead to return to that middle every time because of their weight;

- as the centrally located products rotate, any products stacked on top of and next to them, referred to as "doubles", will in most cases, in cooperation with gutter portions such as plates or also other constructions, lag behind under the influence of friction and try to take up a next upstream empty transport position between two rollers.

Although this manner of singulation and transport has been employed for many years now and has been found to be satisfactory especially in case of substantially round products, the apparatuses as mentioned above nonetheless exhibit shortcomings. The profile of these, generally formulated, rollers with constriction gives rise to:

- unstable rotation of unround products, because the circumferential velocity of a roller at the constriction is considerably less than at a diabolo edge (or cone base end); - at the location of the constriction there is an opening between two successive rollers, where small products can fall through.

These deficiencies hitherto have not been taken into account because the emphasis has been entirely on the ordering in a row, i.e. singulation, of the products. To remedy the above-mentioned deficiencies, the invention provides an apparatus for singulating products supplied in bulk, such as, for instance, fruits, potatoes, or eggs, more particularly for unround products, for instance pears or sweet peppers, comprising:

• an endless conveyor which extends in a transport direction, wherein the conveyor is provided with at least one row, extending in the transport direction, of carriers configured such that between each two successive carriers in the row a transport position for a product is formed, with a first plane extending vertically and through the middle of the respective row of carriers; • wherein each carrier comprises two loose, substantially cylinder- shaped rollers, of which a first is arranged on an associated first pivot and a second on an associated second pivot, wherein the first and the second pivot are each located in a second plane, and wherein the first pivot is situated on a first side of the first plane and the second pivot is situated on a second, opposite side of the first plane;

• wherein the first and the second pivot each include a substantially equal acute angle with the first plane and extend from the first plane slightly obliquely upwards, with the sum of the acute angles being less than 180°; and

• a drive unit for rotating the rollers of the carriers.

It has been found that unround products immediately find their way to the central, lower-situated middle of the transport position without further irregular rotation. Any clearly higher situated "doubles", on the one hand because of their own unstable position near the upper edge of the rollers and on the other hand because of the very stable position of the products that have already taken up their place, will, as a result of the rotating rollers, likewise immediately, try to find an upstream free transport position. Furthermore, the stable central location of the heaviest part of the product that has found its place, for instance the spherical part of a pear, makes it possible, with sensors, to do a representative measurement, for instance a recording for obtaining a spectrum to determine sugar content, water content, or acid content. Further embodiments of the apparatus according to the invention can have as a feature: that the second plane in which the first and the second pivot extend is perpendicular to the transport direction; that the rollers consist of cylindrical brushes; that the cylinder-shaped rollers are arranged to be each individually rotatable around the associated pivot; that the angle with the first plane has a value between 60° and 90°; and/or that the angles on opposite sides of the first plane differ slightly in value.

The apparatus according to the invention will be discussed in detail below, with reference to a drawing, in which Fig. 1 gives a perspective view of an exemplary embodiment of a part of a row of such an apparatus; and

Fig. 2 shows a single roller thereof, which is connected with a link element of a chain.

In the different figures, the same parts have the same numerals. In the exemplary embodiment according to Fig. 1, with an endless roller conveyor 1 products P, for instance, as indicated in the figure, pears, are transported in a transport direction T. This conveyor 1 is formed by inter alia an endless chain driven by an end wheel 2 with drive shaft 3 . It will be clear to those skilled in the art how such a chain is driven, so that further details of this are not represented nor described. As is conventional in this technical field, the products P are conveyed in transport positions which are formed between pairs of successive carriers, the successive carriers situated one after the other in the transport direction forming a row. The conveyor may be provided with several parallel rows of carriers extending in the transport direction T. In this Fig. 1, a single row is represented. Further, in all above-mentioned cases it is conventional for the products at the downstream end of the conveyor 1 to be transferred to a next conveyor, mostly a sorting unit from where the products are released onto packaging lines. Each carrier is formed by a first roller 4a and a second roller 4b.

More particularly, these rollers 4a, 4b are cylinder-shaped. In the exemplary embodiment shown, a first roller 4a is mounted on an associated first pivot 5a and the second roller 4b is mounted on an associated second pivot 5b. The pivots 5a, 5b are arranged on link elements of the chain 2, in particular pivot fastening elements 7, which, furthermore, are in turn connected on both sides with conventional links 6. To those skilled in the art it will be clear that the dimensioning of the parts 4a, 4b, 6, and 7 is determinative of the size of the transport positions, or also the pitch, and hence is determinative of the size of the products P to be conveyed.

The two pivots 5a, 5b are situated on opposite sides of the row, more particularly on opposite sides of a first plane Vl which extends vertically and through the middle of the respective row of carriers, in the transport direction T. Moreover, in an embodiment, these pivots 5a, 5b of a carrier may additionally be located in a second plane V2 which is perpendicular to the first plane Vl. In most cases this second plane V2 is moreover perpendicular to the transport direction T. As indicated in Fig. I₁ the pivots 5a, 5b, and hence also the rollers 4a, 4b, are oriented at an angle α and β, respectively, with respect to the first plane Vl. In an embodiment, the acute angles α, β which the first pivot 5a and the second pivot 5b respectively include with the first plane Vl can be substantially equal. Moreover, the pivots 5a, 5b, viewed from the first plane Vl, extend obliquely upwards, so that the angles included with the plane Vl are acute, i.e. less than 90°. Depending on the products to be processed, these acute angles have a value between 60° and the above-mentioned 90°. A preferred value for such an angle is 75°. What is realized through such a choice for the location of the pivots 5a, 5b is that the transport positions comprise a recessed portion as with trays or cups. These angles may be settable, so that small differences on opposite sides of the first plane Vl are also possible, to thereby obtain more specific movements.

Furthermore, the rollers 4a, 4b may rotate by passing them over a driving track 8. Such driving tracks 8 are known in this area of the art. The tracks 8 may be driven, or also stand still, being pressed against the rollers 4a, 4b and causing the rollers 4a, 4b to rotate through friction between the track surfaces and roller surfaces. With combinations of speeds of the chain 2 and of the track 8, with additional combinations on the left and right, that is, rollers 4a and separately therefrom rollers 4b, all possible movements can be obtained. This transport will generally proceed in a substantially horizontal plane, but in an alternative embodiment it is possible for transport to proceed with a slight rise. What is thus achieved is that in a situation of several products being in the same transport position, rolling back in upstream direction is promoted. Preferably, the pivots 5a, 5b are located in a plane perpendicular to the transport direction T. This simplifies assembly of parts and positioning of drive tracks 8. However, it will be clear to those skilled in the art that in case of any choice of particular angles, there may be technical reasons, for instance roughnesses of plastics used, to place the pivots in a vertical plane, while the transport direction T runs up slightly.

In a further embodiment of the apparatus according to the invention, the rollers can consist of brushes. With this feature, damages to products such as fruit and vegetables, for instance apples, tomatoes, or peaches, can be largely prevented. Furthermore, for particular applications, the rollers 4a, 4b may each be driven separately, for instance for the purpose, in case of delicate products, of driving only those rollers where such is necessary, so that the other products are left alone. Fig. 2 represents in more detail an example of the manner of fastening a roller, being roller 4a in the figure. In this figure, it is clearly indicated how an endless chain 2 of such a conveyor 1 can be assembled, more particularly from combinations of a represented link 6 and a pivot fastening element 7. However, it is also possible that between each pivot fastening element 7 several links 6, for instance two or three, are used, depending especially on the size of the products P to be processed.

In yet another exemplary embodiment, the rollers 4a, 4b of a carrier do not have their pivots 5a, 5b fastened to the same chain in the middle, but two chains are used, one for the rollers 4a on one side of the row and one for the rollers 4b on the other side of the row. This provides entirely the same properties as regards the singulation of the products, while at transfer at the downstream end of the conveyor 1 the products may be delivered to a second conveyor running-along below while the rollers 4a, 4b of a row may diverge gradually.

Claims

1. An apparatus for singulating products supplied in bulk, such as, for instance, fruits, potatoes, or eggs, more particularly for unround products, for instance pears or sweet peppers, comprising:

• an endless conveyor which extends in a transport direction (T), wherein the conveyor is provided with at least one row, extending in the transport direction, of carriers configured such that between each two successive carriers in the row a transport position for a product is formed, with a first plane (Vl) extending vertically and through the middle of the respective row of carriers; • wherein each carrier comprises two loose, substantially cylinder- shaped rollers, of which a first is arranged on an associated first pivot and a second on an associated second pivot, wherein the first and the second pivot of each carrier are each located in a second plane (V2) associated with that carrier and wherein the first pivot (5a) is situated on a first side of the first plane (Vl) and the second pivot (5b) is situated on a second, opposite side of the first plane (Vl);

• wherein the first and the second pivot each include an acute angle (α and β, respectively) with the first plane (Vl) and extend from the first plane (Vl) slightly obliquely upwards, with the sum of said acute angles (α, β) being less than 180°; and

• a drive unit for rotating the rollers of the carriers.

2. An apparatus according to claim 1, wherein the second plane (V2) in which the first and the second pivot extend is perpendicular to the transport direction (T).

3. An apparatus according to claim 1 or 2, wherein the rollers consist of cylindrical brushes.

4. An apparatus according to any one of the preceding claims, wherein the cylinder-shaped rollers are arranged to be each individually rotatable around the associated pivot.

5. An apparatus according to any one of the preceding claims, wherein said angle (α, β) with the first plane (Vl) has a value between 60° and 90°.

6. An apparatus according to any one of the preceding claims, wherein the angles on opposite sides of the first plane (Vl) differ slightly in value.

7. An apparatus according to any one of the preceding claims, wherein said acute angles (α, β) which the first pivot (5a) and the second pivot (5b) respectively include with the first plane (Vl) are substantially equal.