Unknown

Abstract

A sorting device for sorting out discrete products from a product stream includes, a friction element driven by a roller. The friction element is movable to press against a product to be sorted out and thereby apply a frictional force to the product to sort the product out of the product stream.

Claims

1-9. canceled

10. A sorting device comprising: (a) a conveyor for conveying discrete products in a product stream along a conveying path in a conveying direction with the discrete products being supported on a conveyor surface; (b) a first roller defining a first roller circumference and being configured to be driven in a first direction of rotation about a first roller axis; (c) a friction element extending along a portion of the first roller circumference in position to be driven about the first roller as the first roller is driven about the first roller axis, the friction element being moveable in a lifting direction extending transverse to the conveyor surface between a lowered position and a raised position; and (d) wherein the friction element in the lowered position is located relative to the conveyor surface to contact a selected product of the discrete products with a contact pressure force along a contact zone to thereby exert a first direction frictional force on the selected product as the first roller is driven in the first direction of rotation, the first direction frictional force being sufficient to accelerate the selected product in a first sorting direction deviating from the conveying direction to sort the selected product out of the product stream.

11. The sorting device of claim 10 wherein the friction element comprises a friction lining formed integrally with the roller.

12. The sorting device of claim 10 wherein the friction element comprises a structure formed separately from the first roller and mounted on the first roller so as to extend along on the entire circumference of the first roller.

13. The sorting device of claim 10 wherein the friction element comprises a belt that is guided around the first roller and at a second roller and has at least one straight section in a belt longitudinal direction.

14. The sorting device of claim 10 wherein the first roller and with it the friction element are selectively drivable about the first roller axis in a second direction of rotation opposite to the first direction of rotation at least when the friction element is in the lowered position.

15. The sorting device of claim 10 further including a lifting mechanism connected to the first roller and operable to move the first roller in the lifting direction between an upper end position and a lower end position and wherein the lowered position of the friction element corresponds to a position of the first roller at the lower end position or between the lower end position and the upper end position.

16. The sorting device of claim 15 wherein the distance between the upper end position and the lower end position is less than 20 mm.

17. The sorting device of claim 10 wherein at least two of the conveying direction, the first sorting direction, and the lifting direction are orthogonal to each other.

18. A method of sorting discrete products from a product stream being conveyed along a conveying path in a conveying direction while being supported on a conveyor surface, the method including: (a) while a first roller is being driven in a first direction of rotation about a first roller axis to drive a friction element along a portion of the circumference of the first roller, lowering the friction element onto a selected product to be sorted out of the product stream as a portion of the selected product is located on the conveyor surface below the friction element so that the friction element acts on an upper side of the selected product facing away from the conveyor surface along a contact zone of the friction element with a contact force in order to apply a frictional force to the selected product to move the selected product laterally out of the conveying path in a first sorting direction; and (b) after applying the frictional force to the selected product, raising the friction element away from the conveyor surface sufficiently to allow a next product in the product stream to pass under the friction element.

19. The method of claim 18 wherein the coefficient of friction between the conveyor surface and the material of the product supported on the conveyor surface is selected to be smaller than the coefficient of friction between the selected product and the portion of the friction element in the contact zone.

20. The method of claim 18 wherein the friction element is driven at a constant speed between 0.1 m/s and 100 m/s.

21. The method of claim 18 wherein the contact time between the friction element and the selected product is less than 100 ms.

22. The method of claim 18 wherein the friction element is raised away from the conveyor surface along a lifting direction while a portion of the selected product is still located below the friction element with respect to the lifting direction.

23. The method of claim 18 wherein the selected product acted upon by the friction element is moved out of the conveying path orthogonally to the first roller axis.

24. The method of claim 18 wherein the first sorting direction lies at a sorting angle (α) to the conveying direction where (α) is either greater than or less than 90°.

25. The method of claim 18 wherein the first sorting direction lies at a sorting angle of 90° to the conveying direction.

26. The method of claim 18 wherein the product stream is conveyed at a rate of at least 500 discrete products per minute.

27. The method of claim 18 wherein the friction element comprises a belt having a straight section and wherein a portion of the contact zone extends along the straight section of the belt.

28. The method of claim 27 wherein the contact zone extends partially along the straight section of the belt and partially along an arc-shaped section of the belt guided around the first roller.

29. The method of claim 18 wherein the friction element extends around the entire circumference of the first roller and the contact zone extends along an arc-shaped section of the friction element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG. 1 is a schematic side view of a sorting device with conveyor belt.

[0041] FIG. 2 is a schematic partial view looking against the conveying direction X.

[0042] FIG. 3 is a schematic top view looking against lifting direction Z.

[0043] FIG. 4 is a schematic partial view of a modified embodiment, looking against the conveying direction X.

DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

[0044] FIG. 1 shows a simplified side view of a sorting device S according to the invention. Sorting device S comprises a conveyor in the form of a conveyor belt B guided around two rollers. Individual products P, P′ lying on the conveyor belt B are conveyed in a conveying direction X and along a conveying path W, respectively. The products P, P′ are relatively narrow as seen in the conveying direction X and comparatively long in a transverse direction Y orthogonal to the conveying direction X (see also the top view in FIG. 3). For example, such products can be packaged or unpackaged chocolate bars or muesli bars.

[0045] A first roller R is arranged above the conveyor belt B, the roller axis A of which extends parallel to the conveying direction X in this embodiment. An unspecified drive, for example a motor, drives the roller R to rotate via a toothed belt.

[0046] On its outer circumference, the first roller R is provided with a friction element T which is compressible in the radial direction and has a high coefficient of friction. The first roller R is movable in a lifting direction Z between an upper end position Z.sub.o and a lower end position Z.sub.u as indicated by the double arrow via a lifting mechanism H, which is only shown schematically. The lifting direction Z extends orthogonally to the conveying direction X and to the transverse direction Y. With the help of the lifting mechanism H, the first roller R with the rotating friction element T can be lowered towards or raised away from the conveyor belt B in the lifting direction Z. The motor for driving the first roller can be moved along with it or remain stationary as long as the drive of the first roller is ensured continuously (or as necessary to effect a desired product ejection).

[0047] FIG. 2 shows a simplified partial view of the design shown in FIG. 1, looking in the direction opposite the conveying direction X. The first roller R with the friction element T mounted on it is shown in its upper end position Z.sub.o and is driven to rotate in a first direction of rotation D.sub.L. The device is also designed to change the direction of rotation if necessary and to drive the first roller R in an opposite second direction of rotation D.sub.R. It is noted that in the example of FIG. 2 the friction element T extends along a portion of the first roller R comprising the entire circumference of the first roller R.

[0048] Below the first roller R, a product P to be sorted out can be seen, which is being conveyed in conveying direction X and has just reached the X-position below the first roller R. In order to sort out this product P from the product flow, the first roller R and its friction element T is moved towards the lower end position Z.sub.u by means of the lifting mechanism H. This preferably happens very quickly, within a few milliseconds. In the process, the friction element T comes into contact with the surface of the product P. Due to its elasticity in the radial direction, the friction element T can be pressed against the product by a certain amount of pressure Δ, whereby it nestles against the surface of the product P and presses on it along a contact zone K. Depending on the elasticity or compressibility of the friction element T and the force with which the lifting mechanism H presses the first roller R downwards, a frictional force is generated along the contact zone K which acts orthogonally to the roller axis A and ejects the product P from of the product flow in a first sorting direction Y.sub.L (to the left in FIG. 2) (reversing the direction of rotation of the first roller R would result in the opposite sorting direction Y.sub.R).

[0049] In order to sort out the product P in the manner described above, the coefficient of friction μ.sub.PT occurring between the friction element T and the product P must be greater than the coefficient of friction μ.sub.BP occurring between the product P and the surface of the conveying medium B. The greater this difference, the easier it is to move and accelerate the product P with the frictional force generated by the friction element T in order to be ejected from the product flow. The contact time between the friction element and the product is preferably very short and is in the range of milliseconds. As soon as the product has been accelerated sufficiently in the sorting direction to safely leave the product stream, the lifting mechanism H can already lift the first roller R again in order to also sort out or let pass a subsequent further product P′.

[0050] FIG. 3 shows a simplified top view (looking in the direction opposite Z) of how a product P to be sorted out moves in sorting direction Y.sub.L while and after being acted upon by the friction element T of the first roller R. It can also be seen that the sorting direction Y.sub.L encloses a sorting angle α=90° with the conveying direction X. This angle can be changed, if necessary, by the roller axis A making an angle greater than zero with the conveying direction X, since the frictional force created on the product is directed orthogonally to the roller axis A.

[0051] FIG. 4 shows a simplified side view of a modified embodiment of the invention similar to FIG. 2, looking in the direction opposite the conveying direction X. Here, the friction element T is in the form of a soft belt guided around the first roller R and a second roller R′ so as to extend along a portion of the circumference of the first roller R comprising less than the entire circumference of the first roller R. First roller R and second roller R′ are spaced apart in this example by a linkage G. While the second roller R′ is arranged stationary, the first roller R can be moved up and down on a circular path section around the axis of the second roller R′ by means of a lifting mechanism H engaging the linkage G and formed with a pneumatic piston. One of the two rollers R, R′ is driven by a motor, not shown in more detail, so that the friction element T rotates around the two rollers in the first direction of rotation D.sub.L.

[0052] The first roller R can be seen both in its upper end position, which is indicated in FIG. 4 in a solid line, and in its lowered position (shown with a dashed line). By actuating the lifting mechanism H, the friction element T comes back into contact with the product P to be sorted out when the first roller R is lowered in a known manner and applies the resulting frictional force along a contact zone K to the product P to be sorted out, possibly deforming friction element T and/or product P.

[0053] In the embodiment shown in FIG. 4, the product P is essentially impacted by the section of the friction element T on the circumference of the first roller R, which is equivalent to a more point-shaped contact. However, depending on the height of the product and the arrangement of the sorting device, a straight section of the friction element T tangential to the first roller R can also be used to act on the product in the lowered position. In this case, the contact zone K will increase, which will facilitate the generation or transmission of the frictional force. In addition, in this case, the product P is contacted along the straight section and thus in a more linear manner, whereby this line defines the sorting direction Y.sub.L more precisely and thus allows the sorting direction of the impacted product to be specified more accurately.

[0054] As used herein, whether in the above description or the following claims, the terms “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” and the like are to be understood to be open-ended, that is, to mean including but not limited to. Also, it should be understood that the terms “about,” “substantially,” and like terms used herein when referring to a dimension or characteristic of a component indicate that the described dimension/characteristic is not a strict boundary or parameter and does not exclude variations therefrom that are functionally similar. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.

[0055] Any use of ordinal terms such as “first,” “second,” “third,” etc., in the following claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another, or the temporal order in which acts of a method are performed. Rather, unless specifically stated otherwise, such ordinal terms are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term).

[0056] In the above descriptions and the following claims, terms such as top, bottom, upper, lower, vertical, and the like with reference to a given feature are made with reference to the orientation of the structures shown in the drawings and are not intended to exclude other orientations of the structures.

[0057] The term “each” may be used in the following claims for convenience in describing characteristics or features of multiple elements, and any such use of the term “each” is in the inclusive sense unless specifically stated otherwise. For example, if a claim defines two or more elements as “each” having a characteristic or feature, the use of the term “each” is not intended to exclude from the claim scope a situation having a third one of the elements which does not have the defined characteristic or feature.

[0058] The above-described preferred embodiments are intended to illustrate the principles of the invention, but not to limit the scope of the invention. Various other embodiments and modifications to these preferred embodiments may be made by those skilled in the art without departing from the scope of the present invention. For example, in some instances, one or more features disclosed in connection with one embodiment can be used alone or in combination with one or more features of one or more other embodiments. More generally, the various features described herein may be used in any working combination.

REFERENCE SYMBOLS

[0059] A Axis of the roller R

[0060] B Conveyor

[0061] D.sub.L First direction of rotation

[0062] D.sub.R Second direction of rotation

[0063] G Linkage

[0064] H Lifting mechanism

[0065] K Contact zone

[0066] P Product

[0067] P′ The product following product P

[0068] R First roller

[0069] R′ Second roller

[0070] S Sorting device

[0071] T Friction element

[0072] W Conveying path

[0073] X Conveying direction

[0074] Y Transverse direction

[0075] Y.sub.L First sorting direction

[0076] Y.sub.R Second sorting direction

[0077] Z Lifting direction

[0078] Zo Upper end position

[0079] Zu Lower end position

[0080] α Sorting angle

[0081] μ.sub.BP Coefficient of friction between conveyor and product

[0082] μ.sub.PT Coefficient of friction between product and friction element

[0083] Δ Contact pressure dimension