WO2006094837A1

WO2006094837A1 - An arrangement for positioning the longitudinal axis of an onion-shaped product

Info

Publication number: WO2006094837A1
Application number: PCT/EP2006/002348
Authority: WO
Inventors: Wilgert Van Och
Original assignee: Sormac Bv
Priority date: 2005-03-10
Filing date: 2006-03-09
Publication date: 2006-09-14
Also published as: NL1028512C2

Abstract

An arrangement (10) for positioning the longitudinal axis of an onion-shaped product, comprising a first pair of rollers (20) and a second pair of rollers (21) in which arrangement each roller has at least a truncated-cone surface and in each pair the rollers (20, 21) are placed on an axis with the truncated- cone surfaces facing each other and the two pairs of rollers are placed one after the other in a direction perpendicular to their axis, and the rollers (20, 21) of each assembly of four rollers which each time can carry an onion-shaped product can be driven in the same direction, and also that in each assembly of four rollers the conical surface of each roller of a first pair (20) of rollers has a higher coefficient of friction than the conical surface of each roller of a second pair (21) of rollers.

Description

AN ARRANGEMENT FOR POSITIONING THE LONGITUDINAL AXIS OF AN

ONION-SHAPED PRODUCT.

The present invention relates to an arrangement for posi- tioning the longitudinal axis of an onion-shaped product, comprising a first pair of rollers and a second pair of rollers in which arrangement each roller has at least a truncated-cone surface and in each pair the rollers are placed on an axis with the truncated-cone surfaces facing each other and the two pairs of rollers are placed one after the other in a direction perpendicular to their axis, and the rollers of each assembly of four rollers which each time can carry an onion-shaped product can be driven in the same direction.

Such an arrangement is known from British patent application GB 1504997.

In this known arrangement, the onion-shaped products are each time pushed up by the motion of the rollers, so that the products can assume an other orientation. In doing so, there is a risk of the onion-shaped product being pushed up too far, ending up besides the rollers so that it has to be taken as waste.

The object of the invention is to provide an arrangement of the type mentioned in the preamble, avoiding the drawbacks mentioned.

This object is reached according to the invention owing to the fact that in each assembly of four rollers the conical surface of each roller of a first pair of rollers has a higher coefficient of friction than the conical surface of each roller of a second pair of rollers. By giving the conical surfaces different coefficients of friction, the force exerted on the onion-shaped product can be controlled such that this product does not bounce abnormally but is still set in motion at the necessary intensity until it has acquired the correct orientation.

Other features and advantages will become clear from the following description with reference to the appended drawings, in which:

Fig. 1 is a schematic side view of the supply section of an arrangement for positioning onion-shaped products according to the invention, and

Fig. 2 is a top view of the supply section of the onion- shaped products.

For a full understanding of the arrangement for positioning the longitudinal axis of onion-shaped products, the reader is referred to Netherlands patent application 1025386, the content of which is considered to be incorporated herein by reference .

In Fig. 1, a part 10 of the actual arrangement for posi- tioning the onion-shaped products is depicted in a side view, comprising a plurality of pairs of rollers 20 and a plurality of pairs of rollers 21 mounted on an endless chain (not shown) , where each pair of rollers 20 is disposed next to a pair of rollers 21, et cetera. Each roller of any pair of rollers 20 has a surface in the shape of a truncated cone, with the apex angles in each pair of rollers 20 being oriented towards each other. The pairs of rollers 21 have the same shape, but the surface condition of the conical surfaces of the pairs of rollers 20 is dif- ferent from that of the pairs of rollers 21 as will be explained below.

Referring to Fig. 1, the pairs of rollers 20, 21 along with the chain on which they are mounted move to the right in the upper part of their run. Moreover, the pairs of rollers 20, 21 are rotationally driven as described in the above- mentioned Netherlands patent application.

For the proper functioning of the arrangement it is desirable that the onion-shaped products when once they have arrived at the correct orientation are not allowed to dance any longer on the respective two pairs of rollers upon which they rest, but are made to co-rotate.

Furthermore, the arrangement is such that each time an on- ion-shaped product rests in each pair of pairs-of-rollers 20, 21, with the pair of rollers 20, as seen in the direction of motion of the chain, leading the pair of rollers 21.

When the chain is in motion, at least the pairs of rollers 20, 21 bearing onion-shaped products are rotationally driven, with the direction of rotation being counter-clockwise as shown in Fig. 1. Through this motion of the pairs of rollers 20, 21, the on- ion-shaped products are kept in motion as long as they do not have the correct orientation, so that they able to reorient until they have found the correct orientation. If required, this motion can be supported by making use of intermediate parts which partly protrude between the rollers of each pair of rollers 20 and 21, as is described in further detail in the above Netherlands patent application.

The conical surfaces of the pairs of rollers 20 (the leading pairs of rollers) are made such that they have a higher coefficient of friction than the conical surfaces of rollers in the pairs of rollers 21 (the trailing pairs of rollers) according to the invention to achieve an even better control of the motions of the onion-shaped products. This provides a stabler condition, so that it is avoided that the onion-shaped product springs out of the relevant two pairs of rollers 20, 21, since it gives rise to a greater downward force on the onion-shaped product. It has turned out that it is sufficient to make the coefficient of friction of the pairs of rollers 20 at least twice the value of that of the [other] pairs of rollers [21] , but that even better results are obtained when the former coefficient of friction is four times the latter. In practice, this difference in coefficients of friction can be realized in numerous ways.

Accordingly, the conical surfaces of the pair of rollers 21 can be smooth surfaces of a metal, e.g. stainless steel, whereas the conical surfaces of the pairs of rollers 20 can be provided with grooves at an angle with the linear motion of the respective conical surface and at a cross-section which may have various shapes, for example, triangular, rectangular, trapezoid et cetera. Alternatively, it is possible to coat the surface with a special material such as carborundum.

For the supply of onion-shaped products to the arrangement 10, a feed arrangement 30 [also referred to as belt conveyor 30] as shown in Figs. 1 and 2 is used.

The feed arrangement 30 comprises an endless conveying belt 31 which runs over two rollers 131, 32, with the roller 32 being disposed virtually over and near an end of the actual arrangement 10 for orienting the products. In addition, the roller 32 can be driven synchronously with wheel 25 which transmits the drive of the arrangement 10 for orienting the onion-shaped products, and the motion is synchronously- transmitted to the belt 31. The external surface of the belt 31 is equipped with a plurality of projecting parts 35, in the depicted embodiment built up from two pins each time, with a number of these pins, as seen in the longitudinal direction of the belt, being placed at a regular distance from each other. The distance between the pins 35 in each pair is such that they can take an onion-shaped prod- uct in upward motion of the belt 31 without the product falling between the pins 35.

At the lower portion of the belt conveyor 30 there is provided a storage bin 40 comprising a bottom surface 41 which is virtually perpendicular to the surface of the upwardly moving part of the belt 31, and two side surfaces 42, 43 so that said surfaces 41, 42, 43 in combination with the upwards moving part of the belt 31 constitute an open holder 39 capable of containing a certain quantity of onion-shaped products. The wall 41 is provided with recesses allowing the pins 35 to pass.

Mounted on the belt conveyor 30, there are two arms 51, 52 of which the free ends are connected by means of a plate 53. An arm 54 is parallel to the upwardly moving part of the belt 31, is connected with the plate 53 and is kin- e (ma) tically linked with a drive mechanism 55, such as a crank mechanism, which causes the arm 54 to reciprocate, as seen in a direction perpendicular to the top surface of the belt.

The arm 54 also supports a pin 57 extending downwards as far as just over the surface of the upwardly moving part of the belt. The operation of the arrangement is as follows. If the holder 39 contains any quantity of products, then an onion-shaped product will be taken along by each pair of pins 35 each time during motion of the belt 31 through the holder.

In practice, however, it may occur that more than one product is taken along by a pair of pins. To counter this, the pin 57 on the arm 54 moves in synchronization with the belt 31 such that each time when a pair of pins 35 gets in the immediate proximity of the track of the pin 57 it moves at the height of the pair of pins 35, in such a manner that, in the event when a second onion-shaped product is on top of a first one and thus is taken along by the pair of pins, said second product is pushed off and made to roll downward into the holder 39.

So, it is avoided that two onion-shaped products can be introduced virtually simultaneously into the arrangement for orienting and then result in any breakdown. As soon as an onion-shaped product has reached the upper end of the belt conveyor, under the influence of gravity it falls into an assembly of two pairs of rollers 20, 21. Here, too, accurate synchronization of the motion of the belt conveyor 30 and that of the drive wheel 25 is necessary for the onion-shaped product to land exactly in the correct combination of pairs of rollers 20, 21, i.e. leading pair of rollers 20, trailing pair of rollers 21. To avoid that the onion-shaped product lands here at too high a speed, a chute 60 is disposed between the end of the conveyor 30 and the track of the pairs of rollers 20, 21, as a result of which, so to speak, the onion-shaped product will make a smooth landing. In the embodiment shown, above the chute 60 there is provided a stopping device 61 comprising an axle 62 which carries four blades 63 of which the length has been chosen such that they can move precise- Iy along the surface of the chute 60. This stopping device, too, synchronizes with the drive wheel 25 so that an onion- shaped product falling into the chute 60 is stopped by a blade 63 and gets into the correct combination of pairs of rollers 20, 21 in a controlled manner and without much force being involved.

It will be clear that the invention is not limited to the embodiment described and shown in the drawings, but that numerous changes and modifications can be made within the scope of the claims.

Claims

1. An arrangement for positioning the longitudinal axis of an onion-shaped product, comprising a first pair of rollers and a second pair of rollers, in which arrangement each roller has at least a truncated-cone surface and in each pair the rollers are placed on an axis with the truncated-cone surfaces facing each other and the two pairs of rollers are placed one after the other in a direction perpendicular to their axis, and the rollers of each assembly of four rollers which each time can carry an onion-shaped product can be driven in the same direction, characterized in that in each assembly of four rollers the conical surface of each roller of a first pair of rollers has a higher coefficient of friction than the conical surface of each roller of a second pair of rollers.

2. An arrangement according to claim 1, characterized in that the coefficient of friction of the first pair of rollers is at least twice, and preferably four times, the coefficient of friction of the second pair of rollers .

3. An arrangement according to one of the preceding claims, in which the two pairs of rollers in each assembly of four rollers are placed on a means of transport which is driven in one direction, and each pair of rollers is rotationally driven in a direction with the conical surface which supports the onion- shaped product moving locally in a direction opposite to the motion of the means of transport .

4. An arrangement according to claim 3, characterized in that a plurality of assemblies of two pairs of rollers is provided on the means of transport.

5. An arrangement according to claim 4, in which each time two pairs of rollers on the means of transport form an assembly of four rollers for positioning the longitudinal axis of an onion-shaped product, characterized in that in each assembly of four rollers, the first pair of rollers as seen in the direction of motion of the means of transport is provided with conical surfaces having the higher coefficient of friction.

6. An arrangement according one of the preceding claims, in which onion-shaped products are fed to each assembly of four rollers from a storage bin in which the onion-shaped products are supported by a V-shaped bottom of which a portion is formed by an endless belt provided with a plurality of supporting members for onion-shaped product, characterized in that above the endless belt there is provided an arm which moves across the belt surface each time when a setof control members is at a distance the size of approximately an onion-shaped product from the run of the arm.

7. An arrangement according to claim 6, in which the upper end of the endless belt operates in connection with a chute through which the onion-shaped product is fed to the assembly of four rollers, characterized in that above the chute there is provided a stopping device which can be moved over the length of the chute at a controlled speed.

8 An arrangement according to claim 7, characterized in that a plurality of stopping devices is mounted on an axle which can be rotationally driven.

9. An arrangement according to one of the preceding claims characterized in that in the space between the two pairs of rollers there is provided an obstacle capable of moving in relation to the rotation of the rollers .

10. An arrangement according to claim 9, characterized in that the obstacle is a block.

11. An arrangement according to claim 9, characterized in that the obstacle is a freely rotatable roller.

12. An arrangement according to claims 9-11, characterized in that the two pairs of rollers are provided on a means of transport which describes an endless track.

13. An arrangement according to claim 12, characterized in that a plurality of assemblies of two pairs of rollers is provided on the means of transport.

14. An arrangement according to claim 13, characterized in that each set of two adjacent pairs of rollers on the means of transport forms an assembly for positioning the longitudinal axis of an onion-shaped product .

15. An arrangement according to one of the claims 12-14, characterized in that the arrangement comprises two sets of pairs of rollers each being borne by a transport _. arrangement and being driven during a part of the described transport path.

16. An arrangement according to claim 15, characterized in that only in the part of the transport path where the rollers are rotatably driven there is provided an obstacle in the squeeze (waist area) of each assembly of two pairs of rollers.