Sorter

Abstract

A sorter for sorting out discrete products includes an arrangement of adjacent sorting fingers. The sorting fingers, depending on pivoted positions, open a sorting gap in a conveying path for bad products to be sorted out or else close the sorting gap in order to support the further conveying of good products.

Claims

1. A sorter for sorting products from a product stream conveyed in a conveying direction along a conveying plane, the sorter comprising: (a) at least three sorting fingers located beside one another in a transverse direction extending orthogonally to the conveying direction and parallel to the conveying plane, each sorting finger (i) being movable between a respective sorting position and a respective conveying position and having a conveying section oriented along the conveying direction, (ii) when in the respective conveying position the conveying section of the respective sorting finger aligns with the conveying plane for providing support along a portion of the conveying plane, and (iii) when in the respective sorting position the conveying section of the respective sorting finger is removed from the conveying plane so as to form a respective gap in the conveying plane; and (b) a sorting finger actuator system operable for selectively causing each of the sorting fingers to move from its conveying position to its sorting position and then back to its conveying position, the sorting finger actuator system also being operable for causing selected ones of the sorting fingers to sort a designated product out of the conveying direction, the designated product comprising one of the products conveyed in the conveying direction and defining a track along the conveying plane having a track width defined by a dimension of the designated product in the transverse direction, the selected ones of the sorting fingers sorting the designated product out of the conveying direction by each of the selected ones of the sorting fingers moving from its conveying position to its sorting position to jointly form a combined gap that encompasses the track defined by the designated product and that permits the designated product to travel there through and out of the conveying direction.

2. The sorter of claim 1 wherein the selected ones of the sorting fingers comprise a set of less than all of the sorting fingers and the sorting finger actuator system is operable to cause each sorting finger other than the selected ones of the sorting fingers to reside in its conveying position while each selected one of the sorting fingers is moved to its sorting position.

3. The sorter of claim 1 wherein the conveying section of at least one of the sorting fingers includes a conveyor belt.

4. The sorter of claim 1 wherein each sorting finger has a portion thereof raised above the conveying plane when in its sorting position.

5. The sorter of claim 4 wherein the portion of each sorting finger raised above the conveying plane when in the respective sorting position includes a sorting flank having a drivable sorting belt with a sorting belt surface facing in a direction opposite to the conveying direction.

6. The sorter of claim 1 wherein each sorting finger is pivotably mounted at a first end thereof so as to be pivotable about a respective sorting finger pivot axis and wherein when the respective sorting finger is moved from its conveying position to its sorting position the respective sorting finger pivots about its sorting finger pivot axis and lowers a second end of the respective sorting finger below the conveying plane.

7. The sorter of claim 6 further comprising: (a) a number of steering fingers positioned above the conveying plane and beside one another in the transverse direction, each steering finger being movable between a respective steering position and a respective release position; and (b) a steering finger actuator system operable for causing each of the steering fingers to move from its release position to its steering position, the steering finger actuator system also operable for causing at least a selected one of the steering fingers to move from its release position to its steering position to contact the designated product and steer the designated out of the conveying direction and into the combined gap.

8. The sorter of claim 7 wherein the steering finger actuator system is operable to move each steering finger between its release position and its steering position independently of each other steering finger.

9. The sorter of claim 7 wherein each steering finger has a respective steering flank and wherein when a respective steering finger is in its steering position the steering flank of that respective steering finger faces in a direction opposite to the conveying direction.

10. The sorter of claim 9 wherein the respective steering flank of each steering finger has a drivable steering belt with a steering belt surface facing in a direction opposite to the conveying direction.

11. The sorter of claim 7 wherein each sorting finger is movable between its sorting position and its conveying position by pivoting about a sorting finger pivot axis extending in the transverse direction and each steering finger is movable between its release position and its steering position by pivoting about a steering finger pivot axis.

12. The sorter of claim 7 wherein when a respective one of the steering fingers is in its steering position a portion of that steering finger resides in the gap formed by one of the selected ones of the sorting fingers in its sorting position.

13. The sorter of claim 1 further comprising a detector operable to detect the track of the designated product and wherein the selected ones of the sorting fingers are selected responsive to the track detected by the detector so that the combined gap encompasses the track defined by the designated product.

14. A method of sorting out products from a stream of the products conveyed in a conveying direction along a conveying plane, the method comprising: (a) determining a track of a designated product, the designated product comprising one of the products in the stream of the products, wherein the track includes (i) a position of the designated product in a transverse direction extending orthogonally to the conveying direction in the conveying plane and (ii) a width of the designated product in the transverse direction; (b) selecting a subset of sorting fingers from among a set of sorting fingers where the sorting fingers in the set of sorting fingers are located beside one another in the transverse direction, each sorting finger in the set of sorting fingers (i) being movable between a respective sorting position and a respective conveying position and having a conveying section oriented along the conveying direction, (ii) when in the respective conveying position the conveying section of the respective sorting finger aligns with the conveying plane for providing support along a portion of the conveying plane, and (iii) when in the respective sorting position the conveying section of the respective sorting finger is removed from the conveying plane so as to form a respective gap in the conveying plane, wherein each of the sorting fingers in the subset of sorting fingers is selected based upon its location in the track of the designated product so that the subset of sorting fingers jointly encompass the width of the designated product in the transverse direction; and (c) moving each sorting finger included in the subset of sorting fingers from its conveying position to its sorting position to form a sorting gap so that the designated product is sorted out of the stream of the products through the sorting gap.

15. The method of claim 14 wherein the track of the designated product is determined with a camera by image recognition.

16. The method of claim 14 further including determining a position of the designated product in the conveying direction to identify a time at which the designated product reaches the sorting gap responsive to a conveying speed of the designated product.

17. The method of claim 16 wherein the position of the designated product in the conveying direction is determined from camera images of the designated product as it is conveyed in the conveying direction.

18. The method of claim 16 further including determining the conveying speed of the designated product from operational data of a feed belt that conveys the designated product in the conveying direction.

19. The method of claim 14 further comprising: (a) selecting a subset of one or more steering fingers from among a number of steering fingers positioned above the conveying plane and beside one another in the transverse direction, each steering finger being movable between a respective steering position and a respective release position, wherein each steering finger in the subset of one or more steering fingers is selected based upon its location in the track of the designated product; and (b) moving each steering finger in the subset of one or more steering fingers from its release position to its steering position concurrently with moving each sorting finger included in the subset of sorting fingers from its conveying position to its sorting position.

20. The method of claim 14 further comprising determining the track and a track width in the transverse direction repeatedly for each of the products on the conveying plane.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a first embodiment of the invention in partial view with a sorting finger in conveying position;

(2) FIG. 2 shows the view according to FIG. 1 with a sorting finger in sorting position;

(3) FIG. 3 shows the view analogous to FIG. 2 with a sorting belt on the sorting finger;

(4) FIG. 4 provides a simplified side view of an alternative embodiment of the invention with steering fingers;

(5) FIG. 5 shows the view according to FIG. 4 with the steering finger or sorting finger folded down, and

(6) FIG. 6 provides a simplified perspective view of a sorter with sorting fingers and steering fingers.

DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

(7) FIG. 1 shows a simplified side view of a first embodiment of a sorter A according to the invention. The sorter A conveys individual products P.sub.a, P.sub.w in a conveying stream in a conveying direction X. The products are fed—coming from a feed belt K—to a sorting arrangement S. Bad products P.sub.a to be sorted out of the conveying stream are to be discharged through a sorting gap U formed by the sorting arrangement, while good products P.sub.w to be conveyed further are conveyed further in conveying direction X onto a conveying surface F adjoining the sorting arrangement S in a conveying plane E. Each product defines an individual track by its position in the transverse direction Y and its width, along which the product is conveyed on the feed belt K in the conveying direction X (the illustrations of FIGS. 1 to 5 are side views looking in the transverse direction Y, so that the tracks of the products cannot be seen in these illustrations). The upper side of the feed belt K and the conveying surface F lie in a conveying plane E which extends in conveying direction X and in a transverse direction Y extending transversely and horizontally thereto. The vertical direction Z runs orthogonally to both directions X, Y.

(8) The feed belt K and the conveying surface F are spaced apart from each other in the conveying direction X by an intermediate space. The sorting arrangement S is provided in this intermediate space. The sorting arrangement S comprises a plurality of narrow sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . lying closely (and preferably aligned) one behind the other in the transverse direction, of which only one sorting finger S.sub.1 is visible in each of the side views of FIGS. 1 to 5, covering the other sorting fingers S.sub.2, S.sub.3 . . . . The sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . can be pivoted about a common sorting axis J.sub.S extending in the transverse direction Y, each sorting finger being pivotable about the sorting axis J.sub.S from a sorting position S.sub.T into a conveying position S.sub.F and back independently of the other sorting fingers. The pivoting movement can be realized by an unspecified piston-cylinder unit or by another type of actuator or drive known to the skilled person for each individual sorting finger S.sub.1, S.sub.2, S.sub.3 . . . .

(9) FIG. 1 shows the sorting finger S.sub.1 in the conveying position S.sub.F, each sorting finger S.sub.1, S.sub.2, S.sub.3 . . . lying in its respective conveying position, each with an uppermost section in the conveying plane E, so that a good product P.sub.w conveyed by the feed belt K can be conveyed further in conveying direction X to the conveying surface F, supported by the upper side, i.e., section, of the respective sorting finger. The conveying surface F can also be designed as a conveyor belt for removal (discharge belt). In the conveying position S.sub.F, each sorting finger closes a partial gap U.sub.1, U.sub.2, U.sub.3 . . . formed by it between the sorting axis J.sub.S and the feed belt K located upstream thereof, the Y-width of each partial gap U.sub.1, U.sub.2, U.sub.3 . . . corresponding to the width of the respective sorting finger S.sub.1, S.sub.2, S.sub.3 . . . .

(10) The upper run of a driven transport belt not shown in FIGS. 1 and 2 can be arranged on the upper side of the sorting finger in order to support the onward conveyance of the product to the conveying surface F. The transport belt speed is preferably controlled by a control unit to be identical to the conveying speed of the feed belt K and any discharge belt provided downstream.

(11) FIG. 2 shows the sorter A according to FIG. 1, wherein the sorting finger S.sub.1 has been turned up from the conveying position S.sub.F into the sorting position S.sub.T (Some further sorting fingers S.sub.2, S.sub.3 . . . directly adjacent to the sorting finger S.sub.1 have also been swung into the sorting position, which cannot be seen in this view. Further, non-swiveled sorting fingers in the conveying position are not shown in order to provide a better overview). Each sorting finger section swiveled into the sorting position protrudes with a sorting flank M upwards through the conveyor plane E. At the same time, the respective sorting finger S.sub.1, S.sub.2, S.sub.3 . . . opens its partial gap U.sub.1, U.sub.2, U.sub.3 . . . , whereby several directly adjacent partial gaps U.sub.1, U.sub.2, U.sub.3 . . . together, i.e., jointly, form a sorting gap U, in order to discharge a bad product P.sub.a downward through the sorting gap U. In order to eject a bad product P.sub.a from the product stream, those sorting fingers which lie in the track of the respective bad product are each swiveled into their respective sorting position S.sub.T. Further, each sorting finger outside the track adjacent to this in the transverse direction Y can maintain the conveying position S.sub.F in order to be able to continue conveying good products P.sub.w in their respective product tracks onto the conveying surface F.

(12) In the sorting position, the sorting flanks M facing the approaching bad product P.sub.a serve on the one hand to open the respective partial gap U.sub.1, U.sub.2, U.sub.3 . . . . In addition, when the flanks come into contact with a bad product, the flanks apply to the approaching bad product a component of a deflecting force directed perpendicular to the conveyor plane E, in order to force the bad product out of the conveying direction X and down through the sorting gap U. To enhance this effect, a simplified variant shown in FIG. 3 provides the lower run of a driven sorting belt R on the sorting flank M of the sorting finger. The sorting belt R is driven in the direction of the small arrow in order to actively force a bad product P.sub.a contacting the sorting belt downwards through the sorting gap.

(13) The embodiments according to FIGS. 1 to 3 are characterized by the fact that, for sorting, the sorting fingers fold upwards with a section from the conveying position S.sub.F into the conveying path or track of a bad product P.sub.a, so that the respective partial gap U.sub.1, U.sub.2, U.sub.3 . . . and the jointly formed sorting gap U open towards the approaching product. The upwardly projecting section of the sorting finger can perform the dual function of opening the respective partial gap U.sub.1, U.sub.2, U.sub.3 . . . on the one hand and, on the other hand, blocking the conveying path of the bad product P.sub.a in the direction of the conveying surface F in order to divert the bad product. In this case, the sorting axis J.sub.S is located downstream of the partial gaps or the sorting gap U with respect to the conveying direction X.

(14) An alternative embodiment of a sorter according to the invention is shown in FIGS. 4 and 5. There, too, a sorting arrangement S with a plurality of sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . is arranged in an intermediate space existing between the feed belt K and the conveying surface F, which in this respect is analogous to the examples described for FIGS. 1-3. Again, the sorting fingers can be pivoted about a common sorting axis J.sub.S running in the transverse direction Y from respective conveying positions S.sub.F into sorting positions S.sub.T and back. In the conveying positions S.sub.F, they lie with respective uppermost sections in the conveyor plane E. However, in this embodiment the sorting fingers are folded downwards out of the conveyor plane E in order to assume the sorting positions S.sub.T, as can be seen in FIG. 5. The respective partial gap U.sub.1, U.sub.2, U.sub.3 . . . of each sorting finger S.sub.1, S.sub.2, S.sub.3 . . . opens in relation to the conveying direction X downstream of the sorting axis J.sub.S which is the reverse of the embodiment described for FIGS. 1-3. An advantage of this embodiment shown in FIG. 5 is that it is still possible to swivel the sorting fingers even if a feed belt or bad product has already reached the sorting fingers or is resting on them. This increases the flexibility in controlling the sorting fingers and makes it even easier to selectively sort out or convey products that are very close to each other in conveying direction X or in transverse direction Y. However, unlike in the embodiment examples illustrated in FIGS. 1 to 3, the sorting finger cannot be used here to actively divert a bad product. Instead, only gravity acts on the bad product moved into the sorting gap for sorting out. At high conveying speeds, the bad product may therefore not fall sufficiently deep before the end of the sorting gap is reached, and as a result will strike the adjacent conveying surface F.

(15) In order to overcome this disadvantage, the sorter may be equipped with a steering arrangement L arranged above the conveyor plane E, as shown in FIGS. 4-5. Similar to the sorting arrangement, the steering arrangement L comprises a plurality of steering fingers L.sub.1, L.sub.2, L.sub.3 . . . , which may be narrow and arranged one behind the other in transverse direction Y (preferably in alignment), as illustrated, and which are operable to be pivoted about a common steering axis J.sub.L running in transverse direction Y. The steering fingers are also operable to be pivoted independently of one another, for example by means of a piston-cylinder unit or a drive acting in the same way. In respective release positions L.sub.F, the steering fingers L.sub.1, L.sub.2, L.sub.3 . . . lie outside the conveying path of the products so that, in particular, good products P.sub.w can be conveyed under the steering fingers onto the conveying surface F. In a steering position L.sub.L, on the other hand, each steering finger protrudes with a steering flank B into the track of the product(s) to prevent further conveyance of the product(s) onto the conveying surface F. (FIGS. 4 and 5 show only a first steering finger L.sub.1. Further steering fingers lying behind it in the transverse direction Y in the release position or the steering position cannot be seen or are not shown for reasons of clarity).

(16) The steering fingers L.sub.1, L.sub.2, L.sub.3 . . . can be used to actively steer a bad product P.sub.a through a sorting gap U created by sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . located in the corresponding track in the sorting position. Similar to the sorting flanks M of the sorting fingers in the embodiments of FIGS. 1 to 3, a steering finger swiveled down into the steering position L.sub.L generates a component of a deflection force acting downward perpendicular to the conveyor plane on a bad product when it reaches the steering flank B of the respective steering finger.

(17) FIG. 5 illustrates this case. A bad product P.sub.a to be sorted out is to be discharged through a sorting gap U formed jointly by several adjacent sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . . The sorting fingers lying in the track of the bad product P.sub.a are each folded down into their sorting position S.sub.T for this purpose. Furthermore, some of the steering fingers L.sub.1, L.sub.2, L.sub.3 . . . lying in the track of the bad product are folded down from their respective release position L.sub.F into their steering position L.sub.L. The folded-down steering fingers and sorting fingers together form a channel that leads through the sorting gap U. The bad product P.sub.a reaching the sorting gap U is conveyed into and through the sorting gap U by contact with the steering flanks B, in addition to the effect of gravity on the product and is thus sorted out. The movements of the sorting fingers and the steering fingers can be simultaneous or staggered, preferably depending on the conveying speed, the product dimensions or other physical product properties as well as the arrangement of other products (good products and bad products) on the feed belt K.

(18) The number, transverse position, and width of the individual steering fingers L.sub.1, L.sub.2, L.sub.3 . . . do not have to correspond to those of the individual sorting fingers S.sub.1, S.sub.2, S.sub.3 . . . . In an embodiment, the number of steering fingers is smaller than that of the sorting fingers, since not all steering fingers have to be swiveled into the steering position in the track of the product in order to deflect it.

(19) FIG. 6 shows a simplified perspective view of the design according to FIGS. 4 and 5. On the feed belt K, good products P.sub.w to be conveyed further and bad products P.sub.a to be discharged are conveyed to the sorting arrangement S in the conveying direction X. Each product defines its own track. A product Pa to be rejected with the transverse width W.sub.a measured in transverse direction Y is conveyed in its corresponding track T.sub.a. The position of each product is determined by its transverse position Y.sub.P and its longitudinal position X.sub.P, for example relative to the center of gravity or center point of the product relative to a fixed reference point. With the aid of detector D, the current position and/or the associated track on the feed belt may be determined once or repeatedly for each product to be sorted out or conveyed on. The track T.sub.a of the product P.sub.a to be sorted out is indicated in FIG. 6 and is determined by its position and width; the tracks of the other two products are not shown in more detail for reasons of clarity.

(20) In order to be able to discharge the product P.sub.a from the product stream, the sorting fingers of a group G.sub.S (in the present case the subset S.sub.3 to S.sub.8 of the sorting fingers) are folded down from their conveying positions S.sub.F into their sorting positions S.sub.T, thereby jointly forming a sorting gap U in the conveying path of the product P.sub.a. All the other sorting fingers remain in their conveying positions S.sub.F, which includes the group G.sub.S with the sorting fingers S.sub.1 and S.sub.2 on one side of the sorting gap U as well as all the other group of the sorting fingers (not indexed in FIG. 6) on the other side of the sorting gap.

(21) In order to facilitate the discharge, the steering fingers L.sub.4 and L.sub.5 of a group G.sub.L, which lie in the track T.sub.a of the product P.sub.a, are folded down from their release positions L.sub.F into their steering positions L.sub.L by the steering arrangement L with 16 steering fingers positioned above the sorting arrangement S. The product P.sub.a reaching the steering fingers L.sub.4, L.sub.5 is acted upon by these with a downward component of a deflecting force, so that the product in addition to gravity is also actively forced through the sorting gap U. Other good products P.sub.w that are not to be discharged can meanwhile be conveyed further onto the conveyor surface F, which is designed as a discharge belt, via the sorting fingers remaining in their respective conveying position S.sub.F. Accordingly, steering fingers that are not required assume the release position L.sub.F (in the case shown, these are the groups G.sub.L with the steering fingers L.sub.1 to L.sub.3 and L.sub.6 to L.sub.16). Not all steering fingers in the track of a product P.sub.a to be sorted out must be folded down to their respective steering position L.sub.L. Depending on the nature of the product and the conveying speed, it may be sufficient to use only one or two steering fingers for this purpose. These can be, for example, the two middle or the two outer steering fingers of the associated track. If the product is to be discharged safely by gravity alone, there may be no need to operate the steering fingers at all. As soon as a product to be discharged has passed through the sorting gap U, the fingers actuated for this purpose can be folded back up into the release position or conveying position, unless a directly following product to be discharged justifies retaining the previous finger position.

(22) The sorting fingers are equipped with a transport belt R, the upper run of which moves in the conveying direction X at the speed corresponding to the feed belt K and the discharge belt F, in order to be able to convey a good product P.sub.w lying on it in the conveying position S.sub.F or in the sorting position S.sub.T with as little delay as possible.

(23) A control unit H, shown only in simplified form, is used to determine the tracks T.sub.a of the products to be sorted out and their longitudinal positions X.sub.P by evaluating the signals from detector D, which may include a camera and image recognition software, in order to control the appropriate sorting fingers and the steering fingers at a suitable time. The control unit can also process or generate signals relating to the conveyor speed, the product characteristics, the number of rejections, etc., and output or receive them via suitable interfaces. 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.

(24) 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). Rather than using an ordinal term to distinguish between commonly named elements, a particular one of a number of elements may be called out in the following claims as a “respective one” of the elements and thereafter referred to as “that respective one” of the elements.

(25) 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. For an example specific to the following claims, in a structure having a number of sorting fingers, the a limitation that each sorting finger is moveable between one position and another is intended to encompass a structure having a number of sorting fingers that are moveable and also having an additional sorting finger that is not moveable between one position and another.

(26) 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 CHARACTERS

(27) A Sorter B Steering flank D Means of detection E Conveyor plane F Conveying surface G.sub.L Group of steering fingers G.sub.S Group of sorting fingers H Control unit J.sub.L Steering axis J.sub.S Sorting axis K Feed band L Steering arrangement L.sub.1, L.sub.2, L.sub.3 . . . Steering fingers L.sub.F Release position L.sub.L Steering position M Sorting flank P.sub.a Bad product to sort out P.sub.w Good product to convey on R Transport belt S Sorting arrangement S.sub.1, S.sub.2, S.sub.3 . . . Sorting finger S.sub.F Conveyor position S.sub.T Sorting position T.sub.a Track of a product to be sorted out U Sorting gap U.sub.1, U.sub.2, U.sub.3 . . . Partial gap W.sub.a Width of a product to be sorted out in transverse direction Y X Conveyor direction X.sub.P Longitudinal position of a product Y Transverse direction Y.sub.P Transverse position of a product Z Vertical direction