Method for selectively sorting out flowable products

Abstract

In a method for selectively sorting out free-flowing products (4) which are conveyed in a preferably groove-shaped conveying track (3) in a conveying direction (2) along a conveying path (1), the conveyed products (4) are checked by an inspection apparatus in an inspection portion of the conveying path (1). In a sorting-out portion arranged downstream along the conveying path (1), the product (4) that does not fulfil a predefinable inspection criterion is then sorted out and removed from the conveying track (3) by a suction device (8). To do this, the suction device (8) is arranged on the conveying path (1) and a suction flow that flows away from the conveying track (3) is generated for a predetermined suction duration in order to suction-off the product (4) out of the conveying track (3). According to the invention, it is provided that a suction tube (10) of the suction device (8) comprising a suction opening (9) is arranged at a front end (5) of the groove-shaped conveying track (3), in order to suction-off the product (2) that is falling from the conveying track (3) along a fall trajectory (6) at the front end (5) of the conveying track (3) through the suction opening (9).

Claims

1. A method for selectively sorting out free-flowing products which are conveyed in a conveying track in a conveying direction along a conveying path, comprising checking the conveyed products by an inspection apparatus in an inspection portion of the conveying path, and sorting out and removing, by a suction device from the conveying track in a sorting-out portion arranged downstream along the conveying path, products that do not fulfil a predefinable inspection criterion, the suction device being arranged on the conveying path and a suction flow that flows away from the conveying track being generated for a predetermined suction duration in order to suction products that do not fulfil the predefinable inspection criterion out of the conveying track, wherein a suction tube of the suction device has a suction opening arranged at a front end of the conveying track in order to suction-off the products that do not fulfil the predefinable inspection criterion that fall from the conveying track along a fall trajectory at a front end of the conveying track through the suction opening.

2. The method according to claim 1, comprising guiding the suction tube towards the front end of the conveying path before a suction-off process and arranging the suction tube in or on the fall trajectory in order to suction-off the product to be sorted-out while it is falling along the fall trajectory, and moving the suction tube away from the front end of the conveying track after a suction-off process in order not to hinder the falling of a subsequent product in the conveying path that is not intended to be sorted out along the fall trajectory.

3. The method according to claim 1, wherein a collection device, adjacent to the suction opening, for the product to be sorted out is arranged on the suction tube, and the collection device is arranged in the fall trajectory before a suction-off process in order to collect the falling product by the collection device, and the product collected by the collection device is then suctioned-off through the suction opening.

4. The method according to claim 3, wherein the collection device is moved relative to the suction opening after collecting the product to be sorted out in order to facilitate suctioning-off of the product through the suction opening.

5. The method according to claim 1, wherein a suction portion of the suction tube adjacent to the suction opening is oriented at an angle of less than 45° relative to a horizontal plane during a suction-off process.

6. The method according to claim 1, wherein the suction opening of the suction tube of the suction device surrounds the front end of the conveying track at least in portions during the suction-off process.

7. A device for selectively sorting out free-flowing products, comprising a conveying track that extends in a conveying direction as far as a front end of a conveying path, and comprising a suction device comprising a suction tube that opens into a suction opening arranged to suction-off ones of the products that do not fulfil a predefinable inspection criterion from the conveying path, wherein the suction tube is movably mounted at the front end of the conveying path such that the suction tube comprising the suction opening can be moved into or onto a fall trajectory of a product falling from the conveying track at the front end below an upper face of the conveying track and can be moved away from the fall trajectory after a defective one of the products has been suctioned-off.

8. The device according to claim 7, wherein a collection device, adjacent to the suction opening, for the product to be sorted out is arranged on the suction tube.

9. The device according to claim 8, wherein the collection device comprises a trough-shaped or tray-shaped collection region for the product to be sorted out.

10. The device according to claim 8, wherein the collection device comprises at least one air-permeable flow opening, through which a suction flow directed towards the suction opening in the suction tube can flow at least in part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, some exemplary embodiments of the invention which are found in the drawings are shown by way of example and are explained in greater detail. In the drawings:

(2) FIG. 1 is a schematic illustration of the sorting out according to the invention of a product while it is falling from a conveying path.

(3) FIG. 2 is a schematic illustration of the suctioning-off of a product, shown in FIG. 1, at the front end of the conveying path, wherein a suction tube having a suction opening is arranged directly at the front end of a conveying track extending in the conveying path,

(4) FIG. 3 shows a differently designed suction device, in which a collection device adjacent to the suction opening is formed on the suction tube,

(5) FIG. 4 shows a differently designed suction device comprising a collection device, which has an air-permeable flow effect, and

(6) FIG. 5 is a schematic illustration of a differently designed suction device comprising a suction tube, which can be placed onto the front end of the conveying path in a form-fitting manner.

DETAILED DESCRIPTION

(7) FIG. 1 schematically shows a conveying path 1 having a conveying track 3 oriented in a conveying direction 2. Two tablet-shaped products 4 are located in the conveying track 3, which are being conveyed in the conveying direction as far as a front end 5 of the conveying track 3. For this purpose, the conveying path 1 is designed as a vibrating conveyor, such that the products 4 are conveyed in the conveying track 3 in the conveying direction 2 as far as the front end 5 of the conveying track 3 by directed vibrating motions of the conveying path 1.

(8) At the front end 5, the tablet-shaped products 4 fall out of the series of conveyor belts and downwards along a fall trajectory 6 into a packaging container 7 arranged below the front end 5 of the conveying track 3. Here, the fall trajectory 6 corresponds to a flight path of the products 4 which fall from the front end 5 of the conveying track 3 without any external influence and then fall downwards due to gravity.

(9) At the side, a suction device 8 comprising a suction tube 10 that opens into a suction opening 9 is arranged in the immediate vicinity of the fall trajectory 6. In order to sort out a faulty product 4 before it reaches the packaging container 7, which product would otherwise be conveyed into the packaging container 7 by the conveying track 3, a negative pressure can be generated in the suction tube 10 by a negative-pressure-generating device (not shown) such that a suction flow 11 directed into the suction tube 10 is generated in a suction region in front of the suction opening 9. The suction tube 10 is arranged with its suction opening 9 on the fall trajectory 6 such that the suction flow 11 flows through the fall trajectory 6 and a product 4 falling along the fall trajectory 6 is seized by the suction flow 11 and is suctioned into the suction tube 10 through the suction opening 9.

(10) Since the suction tube 10 comprising the suction opening 9 is arranged below the conveying track 3, any undesired impairment of a product 4 that is subsequent to the product 4 to be sorted out and is still located in the conveying track 3 is substantially ruled out.

(11) FIG. 2 schematically shows another variant of the method according to an aspect of the invention. The suction tube 10 comprising the suction opening 9 is guided towards the front end 5 of the conveying track 3 immediately before the start of a suction-off process and is arranged such that the fall trajectory 6 of a falling product 4 would pass through the suction opening 9. The product 4 to be sorted out is already conveyed towards the suction opening 9 while being conveyed in the conveying track 3. A suction portion 12 adjacent to the suction opening 9 has a small angle of less than 20° relative to a horizontal plane or relative to the orientation of the conveying track 3. When the suction tube 10 and the suction opening 9 are arranged in this way, just a low suction flow 11 having a comparatively low suction power is sufficient to suction the product 4 to be sorted out into the suction tube 10 through the suction opening 9 at the front end 5 of the conveying track 3 with assistance from the suction flow 11. Owing to the very low suction flow 11 having a low suction power in this configuration, any undesired influence on a subsequent product 4 can likewise be prevented.

(12) Once the suction-off process for the product 4 to be sorted out is completed, the suction tube 10 comprising the suction opening 9 is removed from the front end 5 of the conveying track 3 again. The subsequent product 4 can then fall undisturbed along the fall trajectory 6 and can fall into a packaging container or a subsequent conveying path, for example.

(13) FIG. 3 shows a differently designed suction device 8. A tray-shaped collection device 13, adjacent to the suction opening 9, is formed on the suction tube 10. The suction tube 10 can be arranged with the collection device 13 below the conveying track 3 such that the fall trajectory 6 leads into the collection device 13, or continues through the collection device 13. The product 4 falling along the fall trajectory 6 at the front end 5 then falls into the collection device 13 and can be suctioned through the suction tube 10 out of the collection device 13 with a suction flow 11 having a low suction power. In order to prevent products 4 that are not to be sorted out from being impaired or even sorted out when falling along the fall trajectory 6, the suction tube 10 comprising the collection device 13 has to be moved into the fall trajectory 6 immediately before the start of a sorting-out process and then has to be moved out of the fall trajectory 6 again. When using a suction device 8 comprising a collection device 13, the suction-off process can also start slightly later if the product 4 has already been collected by the collection device 13. Optionally, it is also possible for the suction-off process not to start until the suction tube 10 comprising the suction opening 9 and the collection device 13 has already been removed from the fall trajectory 6 again.

(14) FIG. 4 shows, by way of example, a differently designed collection device 13 on the suction tube 10. The collection device 13 comprises a grating 15 fixed to a frame 14, which grating forms an air-permeable flow opening 16. During the suction process, the suction flow 11 can be suctioned through the grating 15 and thus through the flow opening formed by the grating 15, such that the suction flow 11 can be suctioned into the suction tube 10 through the flow opening 16 virtually unimpeded and without turbulence. A product 4 lying on the grating 15 in the collection device 13 can be suctioned with a comparatively low suction power.

(15) In the configuration of the suction device 8 shown by way of example in FIG. 5, the suction tube 10 has a shape that is adapted to the shape of the front end 5 of the conveying track 3 in the region of the suction opening 9. The majority of a cross-sectional area of the suction opening 9 covers the front end 5 of the conveying track 3. Only a small proportion of less than 20%, preferably less than 10%, of the cross-sectional area of the suction opening 9 projects laterally along the conveying track 3 and forms a stop surface 17, which can be used a guide and positioning aid during a movement of the suction tube 10 before and after a suction-off process.