Method for identifying and tracking individually delivered products

Abstract

The method involves recognizing and tracking individually conveyed products (4) which are cylindrical in at least some regions and have a circumferential surface (8) to which a mark (10) is applied individually. The products (4) are conveyed by a transport device (2) in a transport direction (T) and are rotated during the conveying by a friction element (20) which engages by friction with each product (4) as it is being conveyed. Finally, the mark (10) applied to the circumferential surface (8) of each product (4) is read by a stationary camera system (16) having at least two lenses (18) as the respective product (4) is being rotated.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for identifying and tracking individually conveyed products. BACKGROUND

[0002] Many products, in particular in the pharmaceutical sector, are provided with optical markings (two-dimensional codes, data matrix codes, etc.) to enable the individual products to be clearly identified and tracked.

[0003] If these markings are to be scanned during the conveying of the products, the products must be aligned with respect to the respective lens, with the marking facing the lens, or, in the case of products without a predetermined orientation, the products must be examined by the lens from different sides. SUMMARY

[0004] It is an object of the present invention to ensure stable identification of markings applied to products without a predetermined orientation using as few devices as possible while the products are being transported.

[0005] According to one aspect of the invention, the method for identifying and tracking individually conveyed products, in particular medical products, such as syringes, ampoules, vials or inhalers, comprises the following steps, wherein the individually conveyed products are at least partially rotationally symmetrical, in particular cylindrical, and have a circumferential surface to which a marking, in particular a code, is applied:

[0006] - conveying the products in a conveying direction by means of a transport device, wherein the transport device has a plurality of successive chambers for receiving an individual product each, wherein each product is received rotatably in the associated chamber,

[0007] - during the conveying, rotating each product by means of a friction element, which engages each product by friction, in particular static friction, while the product is being conveyed, and

[0008] - reading the marking applied to the circumferential surface of each product by means of a stationary lens system having at least one lens while the respective product is being rotated.

[0009] This method ensures stable identification of markings on products without a predetermined orientation during the conveying. The products are received without a predetermined orientation in the chambers of the transport device, and the orientation of the markings in the chambers of the transport device is therefore random. Only by rotating the products can all parts of the circumferential surface of the products be presented to the lens system, and each product must be rotated at least one full 360° in front of the lens system to ensure that each marking is detected by the lens system.

[0010] The effect of the friction element on the product is similar to a mechanical brake. Since the product is mounted rotatably, it will rotate and roll on the friction element.

[0011] In a preferred embodiment, the friction element is arranged in a fixed position. This makes the structural design particularly simple. During the conveying, each product rolls on the stationary friction element and thus provides a specific circumferential portion of the circumferential surface of the lens system for the inspection when rotating. The friction element can also be moved and then preferably runs in the opposite direction to the product transport at a constant speed.

[0012] In a preferred embodiment, the friction element is a belt. It is also conceivable to be a rotating belt, a rotatable roller or a rotatable disc.

[0013] In a particularly preferred embodiment, the friction element has an elastomer material at least on the side facing the product. The elastomer is deformed by the passing product and the product is particularly stably moved in rotation by means of the static friction.

[0014] Preferably, the engagement of the friction element with the product for rotating each product takes place in the area of the circumferential surface of the product, so that a continuous and safe rotation of the product is ensured.

[0015] To ensure a safe and uniform rotation of each product without slipping, the coefficient of friction between the friction element and the product material is preferably at least 0.2, more preferably at least 0.3 and particularly preferably at least 0.4. In this case, the friction value is determined in accordance with DIN ISO 8295 since 1995.

[0016] The container of each chamber preferably has a shaped recess, by means of which the product can be held in its position.

[0017] Each product is preferably supported counter-gravitationally in its container and the rotating product is rotated about an axis of rotation of the product. The axis of rotation of the product is usually perpendicular to the transport direction. To support the product counter-gravitationally in its container, for example a product flange can be used, which is supported 360° on one or more shoulders of the container during the entire product rotation. It is also conceivable that the product base is supported on a support base of the chamber.

[0018] In each case, the product is preferably mounted in the container with its axis of rotation on the roller, for example parallel to the axis of rotation of the product. In a particularly preferred embodiment, the circumferential surface of the product is in contact with the roller. This minimizes the friction between the product and the chamber. Alternatively / additionally, it is conceivable to provide further measures to make the product slip easily when rotating in the chamber and to reduce the coefficient of friction between the product and the container. For example, the shoulders or the support base of the chamber can have a hard and smooth material at least on the side facing the product.

[0019] In a preferred embodiment, the conveying takes place at a uniform translational speed and the rotation takes place at a uniform rotational speed. This makes it possible for the markings to be stably sensed by the lens system and for the recorded lens images to be evaluated easily.

[0020] The translation speed of the product can be as low as 1 mm per second in principle, but it is usually preferred to be at least 10 mm per second, more preferably at least 60 mm per second, and especially preferably at least 100 mm per second.

[0021] The diameter of the rotationally symmetrical region of the product is preferably 5-40mm, and even more preferably 6-30mm.

[0022] The product's rotational speed is typically 0.08-8 revolutions per second, preferably 0.1-6 revolutions per second, more preferably 0.5-6 revolutions per second, and particularly preferably 1-6 revolutions per second.

[0023] The lens system may have a single lens. However, it is preferable to have multiple lenses, arranged continuously in the transport direction and preferably in a row, but with at least first and second lenses. This allows for higher product throughput and faster transport speeds than a single lens, since each individual lens only needs to check for markings on a portion of the circumferential surface of the product. In a preferred embodiment, the lens system may have three, four, or even more lenses. Product rotation is preferably performed continuously throughout the entire lens system area, i.e., along all existing lenses.

[0024] In this scenario, it is preferable that the effective fields of view of multiple lenses do not spatially overlap within the product area. This helps eliminate duplicate sensing of a mark by multiple lenses.

[0025] A lens's "effective field of view" is designed to correspond to its actual field of view. Alternatively, with appropriate software settings, the lens's actual field of view can be limited to the desired effective field of view, thus recording or evaluating only the content within that area.

[0026] The effective field of view of each lens can be, for example, rectangular. Within the product area, the width of the "effective field of view" of each lens typically does not exceed the corresponding equal distance between the two compartments of the transport equipment, preferably reduced by 10-60%, and more preferably by 20-40%. This ensures that at any given time, at most one product mark is identified within the effective field of view of the lens, without identifying any other marks on a second product. Alternatively, with the aid of a single lens, two marks on consecutive products may also be read simultaneously.

[0027] For safety reasons, the height of the effective field of view of each lens is usually selected to be slightly higher than the marked height, for example, 30% to 150% higher.

[0028] When markings are placed on a product with a rotational angle between + / -30° and the central zero line, and sometimes even only between + / -20° or + / -15°, it is generally possible for a lens to identify the markings on the circumferential surface of the product. In this case, the central zero line corresponds to a line on the product, and the lens's field of view is perpendicular to that line at a specific point in time.

[0029] In principle, it's possible to keep the effective field of view of each shot continuously active and thus always record images within that field of view. However, it's advantageous if each shot is only activated intermittently. This eliminates the need to record images at irrelevant points in time.

[0030] In these cases, the time interval for the lens to record images is usually no more than the time it takes for the transport equipment to travel the distance between the two chambers, preferably shortened by 1-30%, and more preferably shortened by 2-25%.

[0031] The active time of each lens is preferably substantially consistent with the time period during which the product appears within the effective field of view of that lens. The active time of each lens is preferably predetermined externally by the controller, for example, by the programmable logic controller of the overall system, which knows the corresponding position of each product.

[0032] When using multiple lenses, it is generally preferable that one upstream lens, by identifying a specific product, deactivates all downstream lenses during the passage of that product. Furthermore, when a specific lens detects the mark, that lens is also preferably deactivated until a new product enters its effective field of view or the field of view is reactivated by the next product. In this document, "deactivation" means that the lens's image recording is turned off or that the recorded image data is not evaluated.

[0033] Preferably, the relationship between the translational speed of the transport equipment, the diameter of the rotationally symmetrical region of the product, the distance between the transport equipment compartments, the width of the effective field of view of the lens within the product area, and the distance between the lenses is set in such a way that the second circumferential portion of the product detected by the effective field of view of the second lens during product rotation differs from the first circumferential portion of the product detected by the effective field of view of the first lens during product rotation. In this regard, if the lenses do not continuously record images, the active time of each lens must also be appropriately coordinated with other parameters.

[0034] In this case, the first and second circumferential portions preferably overlap in the circumferential direction marked at least in the rotationally symmetric region. If there are exactly two lenses, it is useful for the corresponding overlap on the two edges of the circumferential portions.

[0035] If there is a third lens, the third circumferential portion of the product detected by the effective field of view of the third lens during product rotation should be different from the first and second circumferential portions of the product. If there is a fourth lens, the fourth circumferential portion of the product detected by the effective field of view of the fourth lens during product rotation should be different from the first, second, and third circumferential portions of the product. This also applies to any other lenses that may be present. In each case, preferably, one of the circumferential portions covered by one of the lenses overlaps with the other two circumferential portions at least by the rolling distance marked in the circumferential direction of the rotationally symmetric region. Overall, the multiple lenses thus collectively cover the entire periphery of the circumferential surface of the product and overlap in each overlapping area. This achieves maximum throughput while ensuring stable operation.

[0036] Preferably, the evaluation frequency of at least one lens is in the range of 20-60 images per second, and more preferably in the range of 30-50 images per second.

[0037] The markings are preferably 2D encoded, especially QR codes or data matrix codes. However, other commercially available markings that can be optically identified are also conceivable.

[0038] The marking is typically arranged along the circumferential surface of the product, and therefore appears curved in the circumferential direction of the circumferential surface.

[0039] The lens of the lens system is preferably a digital image acquisition device or an encoder reader.

[0040] The predetermined distance between continuous compartments of transport equipment is usually in the range of 20mm-100mm, and more often in the range of 20mm-65mm.

[0041] The distance between the lens and the product is usually 50mm-120mm, preferably 60mm-80mm.

[0042] The distance between two consecutive lenses is usually 50mm-150mm, preferably 70mm-100mm.

[0043] The evaluation and / or decoding of recorded images and / or encoding can be performed in an integrated evaluation unit within the lens system itself or in an external evaluation unit. This can be, for example, part of the machine controller or providing data to it.

[0044] Product and label assignment is typically performed in a higher-level system, such as a programmable logic controller.

[0045] The encoded data content can be decoded in the shift register and / or transmitted to the controller and / or to the database before being allocated to the product. Attached Figure Description

[0046] Figure 1This is a perspective view of a device used to implement one embodiment of the method according to the invention.

[0047] Figure 2 yes Figure 1 Top view of the equipment.

[0048] Figure 3a It is a cross-sectional view of the transport equipment room containing the received products.

[0049] Figure 3b correspond Figure 3a However, it includes additional geometric details.

[0050] Figure 4 An image that may be recorded by a lens is shown in one embodiment of the method according to the invention. Detailed Implementation

[0051] Figure 1 A system that may be used to implement one embodiment of the method according to the invention is presented.

[0052] In transport device 2, products 4, particularly medical products such as syringes, ampoules, vials, or inhalers, are individually and continuously conveyed in the transport direction T at a constant translational speed. Transport device 2 has individual chambers 6, in each of which products 4 are received into a container 7. All individual chambers 6 are identical in design. The individual chambers 6 are spaced equidistant from each other by a distance D (see...). Figure 2 Each product 4 has a circumferential surface 8 in certain areas, on which a mark 10 is typically applied, for example, as a label pasted or printed directly in each case.

[0053] Product 4 is initially received into chamber 6 by rotation in any orientation. Each product 4 will therefore typically have a different orientation. In this example, product 4 is in the form of a syringe with product flange 12 resting on the shoulder 14 of the corresponding chamber 6, where product 4 is supported against gravity. In this case, product 4 is suspended vertically in the corresponding container 7.

[0054] Product 4 is guided in the transport direction T through lens system 16, which in this example consists of four lenses 18. The individual lenses 18 are arranged so that they can move relative to each other in the transport direction T to ensure optimal setup for different products 4 or product forms. However, during operation, these lenses remain stationary in their preset positions.

[0055] During the translation of product 4, product 4 comes into contact with friction element 20. Friction element 20 specifically uses a stationary belt, which has an elastomeric material on its side facing product 4 that engages with each product 4 through friction, specifically static friction. Friction element 20 is adjustable, thus accommodating different product forms. Friction element 20 directly contacts the circumferential surface 8 of product 4 and causes product 4 to rotate uniformly about the rotation axis 22 of each product 4. This rotation axis is perpendicular to the transport direction T. The rotation direction is determined by… Figure 3a The arrow R in the diagram represents...

[0056] from Figure 2 As can be seen, each lens 18 has an effective field of view 24, within which the mark 10 of product 4 can be recorded. The effective fields of view 24 of the individual lenses 18 preferably do not overlap. An example of the effective field of view 24 of the lens 18 within the product 4 area is shown in... Figure 4 The maximum field of view is presented by the inner rectangle or lens 18, which is part of a larger image area.

[0057] from Figure 1 As can be seen, the system also includes an evaluation unit 26 for the images recorded by lens 18 and a controller 28, to which the data of the evaluation unit 26 is transmitted. The control unit 28 can simultaneously be responsible for the operation of the transport equipment 2 or at least receive information items regarding the operation of the transport equipment 2. The controller 28 can also trigger the active interval of each lens 18.

[0058] As the individual product 4 passes along the friction element 20 and rotates, the markings 10 applied to the circumferential surface 8 of each product 4 are read by means of the lens 18 of the lens system 16. Figure 3a and 3b It can be seen that each product 4 in the container 7 of the corresponding chamber 6 is preferably mounted on a roller 30, the rotation axis 31 of which is parallel to the rotation axis 22 of the product 4.

[0059] Each lens 18 identifies the mark 10 only within a specific rotation angle range around the vertical zero line 36 on both sides, and the line of sight 38 of the lens 18 is perpendicular to this line. Figure 3b ).exist Figure 3b In this context, this angular range is indicated by reference mark 32. This angular range 32 depends on the diameter 34 of the product 4 and is typically 60° or less in total. The frequency of image recording for each lens 18 must be high enough to achieve at least one recording of the complete mark 10 within this angular range.

[0060] The individual lenses 18 are arranged such that the translational speed of the transport device 2, the diameter 34 of the rotationally symmetrical region of the product 4, the distance D between the chambers 6 of the transport device 2, the width B of the effective field of view 24 of the lens 18 within the product 4 region, and the distance between the lenses 18 are arranged in such a way that the circumferential portion of the product 4 detected by each lens's effective field of view 24 during the rotation of the product 4 is different from the circumferential portion of the product 4 detected by the effective field of view 24 of the other lenses 18 during the rotation of the product 4. In this case, each effective field of view 24 of the lens 18 preferably overlaps with the extension of the mark 10 in the circumferential direction of the circumferential surface 8. Therefore, regardless of the original orientation of the product 4, the lenses 18 collectively cover the entire periphery of the circumferential surface 8 of the product 4. The overlap of the effective fields of view 24 is used to ensure that the complete mark 10 can be read within at least one effective field of view 24 of the lens 18.

[0061] For efficiency reasons, the width B of the effective field of view 24 of each lens 18 within the product 4 area is preferably as large as possible. At the same time, it is ensured that only one mark 10 can be read at a time within the effective field of view 24 of the lens 18.

[0062] from Figure 4 As can be seen from the recorded image, the width B of the effective field of view 24 within the product 4 area presented in the example is chosen such that while the second mark 10 of another product 4 has appeared at the right edge of the effective field of view 24, the first mark 10 of the first product 4 is still at the left edge of the effective field of view 24. However, the mark 10 located at the right edge cannot yet be read by the lens 18 due to its rotational position relative to the lens 18. Therefore, the scenario shown illustrates the limiting situation of the maximum width B of the effective field of view 24 if the lens 18 is to recognize only one mark 10 in the recorded image.

[0063] Lens 18 may also have detected the entire periphery of the circumferential surface 8 of the product 4 within its effective field of view 24, depending on the geometric parameters described in more detail above. However, due to the need for high throughput, two to four lenses 18 are typically required.

Claims

1. A method for identifying and tracking individually delivered products (4), wherein the individually delivered products (4) are at least partially rotationally symmetrical and have circumferential surfaces (8) to which marks (10) are respectively applied, characterized in that, The method includes the following steps: - The product (4) is conveyed in the transport direction (T) by a transport device (2), wherein the transport device (2) has a plurality of consecutive chambers (6), each chamber (6) receiving one of the products (4), wherein each product (4) is rotatably received in the relevant chamber (6). - During transport, each product (4) is rotated by a friction element (20). While the product (4) is being transported, the friction element engages with each product (4) through friction. - While the corresponding product (4) is being rotated, a mark (10) applied to the circumferential surface (8) of each product (4) is read by a stationary lens system (16), the stationary lens system (16) comprising a plurality of lenses (18) but at least a first and a second lens, the lenses being arranged continuously in the transport direction (T). -The translation speed of the transport equipment (2), the diameter (34) of the rotationally symmetrical region of each product (4), the distance (D) between the chambers (6) of the transport equipment (2), the width (B) of the effective field of view (24) of each lens (18) in the product (4) region, and the relationship between the distances between the lenses (18) are set in such a way that the second circumferential portion of each product (4) detected by the second effective field of view of the second lens during the rotation of the product (4) is different from the first circumferential portion of each product (4) detected by the first effective field of view of the first lens during the rotation of the product (4); -The first and second circumferential portions overlap at least in the circumferential direction of the rotationally symmetric region of the product (4) with the extension of the mark (10); the first and second effective fields of view (24) do not overlap spatially within the product (4) region; The width (B) of the first and second effective fields of view (24) within the product (4) area is 10-60% smaller than the distance (D) between the two chambers (6) of the transport equipment (2).

2. The method according to claim 1, characterized in that, The friction element (20) is stationary.

3. The method according to claim 2, characterized in that, The friction element (20) is a strip.

4. The method according to claim 1, characterized in that, The friction element (20) has an elastomeric material on the side facing the product (4).

5. The method according to claim 1, characterized in that, Each product (4) is supported against gravity inside the container (7) of the chamber (6), and the rotating product (4) is carried out around the axis (22) of the product (4) which is perpendicular to the transport direction (T).

6. The method according to claim 1, characterized in that, Each product (4) is mounted on a roller (30) in a corresponding chamber (6) container (7), wherein the axis of rotation (31) of each roller (30) is parallel to the axis of rotation (22) of the product (4).

7. The method according to claim 1, characterized in that, The transmission is carried out at a uniform translational speed and the rotation is carried out at a uniform rotational speed.

8. The method according to claim 1, characterized in that, The image recording frequency of several of the shots (18) is in the range of 20-60 images per second.

9. The method according to claim 1, characterized in that, The time interval for recording images of each of the multiple lenses (18) is 1-30% shorter than the time interval for the transport equipment (2) to advance the distance (D) between the two chambers (6).

10. The method according to claim 1, characterized in that, The translation speed of the transport equipment (2) is at least 60 mm per second.

11. The method according to claim 1, characterized in that, The translation speed of the transport equipment (2) is at least 100 mm per second.

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