Separating and gripping device

Abstract

For certain situations, it is necessary to have a gripping device (1) which is capable of separating layers (3) of flexible materials, and then picking them up and processing them. Known gripping devices simply have suction openings (4) for this. If such a suction opening is used, separation is quite difficult to achieve. It is, indeed, known to check separation using the transmitted-light method but if this is unsuccessful the knowledge in this respect is of no further assistance. Against this background, the gripping device (1) according to the invention provides a cost-effective way, with the additional use of the Coanda effect, of creating a rapid and reliable method of separation, and subsequent pick-up for processing purposes, by applying air under suction perpendicularly to layers of material and blowing it out at an obtuse angle thereto such that the raised material layers begin to flutter and, if a number of layers have been attached, separate.

Description

[0001] SINGLING AND GRIPPING DEVICE

[0002] The present invention relates to a gripping device comprising a receiving body for separating and receiving layers of a flexible material to be separated, wherein the receiving body is assigned at least one radially oriented suction opening for the adhesion of the layers to be separated, wherein the receiving body is assigned at least one discharge opening oriented substantially tangentially to a surface of the receiving body for separating individual layers of flexible materials, wherein the at least one discharge opening is connected to at least one overpressure line and the at least one suction opening is connected to at least one underpressure line, wherein the overpressure line and the underpressure line traverse the receiving body at least sectionally in the longitudinal direction.

[0003] Such a gripping device is already known from DE 102 58 896 A1. Further reference is made to DE 10 2012 215798 A1 and EP 3 572 362 A1.

[0004] WO 2021 / 003141 A1 also describes a gripping device. Here, individual layers are separated on a stationary surface. The roller has only one suction opening. It is a separating device for fabric layers with a stationary cylindrical body and an airflow between the cylinder surface and a stack of fabric. The resulting negative pressure draws in the top layer, which is detected by a sensor. Holding fingers are then activated to secure the layer.

[0005] Such gripping devices are already used in the prior art. A common problem when handling flexible materials is that, especially after a multi-layer cutting process of several flexible sheet materials, separating individual layers is difficult because several layers often adhere to one another. If several layers are picked up simultaneously, they can easily fall off during transport. The invention therefore provides for the targeted handling of a single layer of a flexible material. 322028-EP-PCT / 29.07.2025 / nc / mw

[0006] - 2 -

[0007] The system uses suction to pick up materials or sheet materials and, after suction, grips them with a fold-out clamping finger to securely hold each individual layer. Either the clamping finger or the pickup roller has a light source and corresponding light sensor that generates transmitted light, which is then evaluated on the opposite side. Based on the measured light intensity, it is determined whether exactly a single layer has been picked up. However, if it is not a single layer, the only option is to release the layer and try to pick it up again.

[0008] Additionally, a sensor detects whether multiple layers have been gripped. Furthermore, documents US 11,161,705 B2, DE 38 16 250 A1, EP 1 032 534 B1, and EP 0 437 484 B1 reveal a suction gripper with an additional clamping device. This device incorporates an optical sensor that detects the presence of a textile layer. However, there is no indication that the sensor can distinguish the number of fabric layers.

[0009] Against this background, the present invention is based on the objective of creating a gripping device which is able to achieve a safe singulation of layers of flexible material to be singulated using simple means.

[0010] This is achieved by a gripping device according to the features of independent claim 1. Useful embodiments of such a device can be found in the subsequent dependent claims.

[0011] The device provided is a gripping device comprising a receiving body for separating and receiving layers of a flexible material to be separated, wherein the receiving body has at least one radially oriented suction opening for the adhesion of the layers to be separated, and wherein the receiving body has at least one discharge opening oriented substantially tangentially to a surface of the receiving body. 322028-EP-PCT / 29.07.2025 / nc / mw

[0012] - 3 -

[0013] The separation of individual layers of flexible materials is associated with the at least one blow-out opening being connected to at least one overpressure line and the at least one intake opening being connected to at least one underpressure line, wherein the overpressure line and the underpressure line traverse the receiving body at least section by section in the longitudinal direction, characterized according to the invention in that the receiving body is designed as a radially movable receiving roller.

[0014] While air is drawn in through the vacuum line perpendicular to the outer wall of the receiving body, holding the flexible material in place, air is simultaneously expelled through the tangential discharge openings, which are arranged at an obtuse angle to the intake openings. This expulsion pushes the material away from the receiving body. The material begins to flutter, a phenomenon known in the prior art as the Coanda effect. Since each layer of material is individually excited into a wave-like motion, adhering layers move differently, allowing them to be separated. This simple method ensures that only a single layer of material adheres to the receiving body.

[0015] A fully automated process significantly increases efficiency. Furthermore, the use of positive air pressure is easy to implement and, especially compared to suction nozzles, requires considerably less maintenance, as the intake and exhaust openings are less prone to clogging. This significantly reduces downtime and maintenance work, thereby dramatically increasing throughput and efficiency. It also ensures that only one layer is picked up at a time.

[0016] In a first concrete embodiment, the receiving body can be designed as a radially movable, i.e., rotatable, receiving roller. This allows the receiving body to be operated via a 322028-EP-PCT / 29.07.2025 / nc / mw

[0017] - 4 - the layer of material to be received can be unrolled and adhered to the receiving body, whereby part of the material layer is removed from the remaining layers of material due to adhesion and further rotation.

[0018] Preferably, such a radially movable receiving roller can be elliptically shaped, in particular round. This allows a single layer of flexible material to be wound along the outer contour of the receiving roller, thereby ensuring the reliable reception of individual layers.

[0019] Additionally, the receiving roller can be divided into at least two, preferably four, roller segments, with at least one roller segment having an overpressure line and an underpressure line. Dividing the receiving roller into multiple roller segments makes maintenance easier in the event of a failure and reduces production costs, as this element can be mass-produced and then simply assembled into a complete receiving roller.

[0020] Preferably, the roller segments can be made of plastic or coated with plastic. This ensures adhesion along the longitudinal axis of the receiving roller, resulting in optimized performance. It also makes manufacturing more cost-effective.

[0021] In a specific design, it appears advantageous if the roller segments are constructed around a groove profile with undercut grooves, with each roller segment having fastening elements that are received in the undercut grooves of the groove profile. This enables simple assembly and also allows for quick replacement in the event of a failure, thereby reducing downtime and increasing production throughput. 322028-EP-PCT / 29.07.2025 / nc / mw

[0022] - 5 - can be increased. The fastening means can be, for example, screwed-on or molded T-nuts or a longitudinally extended insert, which can be positively inserted into the groove of the T-profile from the end face.

[0023] In a specific embodiment, at least one drive can be assigned to the end of the groove profile, rotating the receiving roller around its longitudinal axis. This allows for fully automated rotation of the receiving roller without significant additional effort. If present, a drive can be attached to the groove profile, which can be mechanically connected to a motor shaft without difficulty.

[0024] Preferably, the positive pressure line and the negative pressure line of a roller segment can be connected to a pressure distributor. This significantly reduces the number of pressure lines. Particularly in the case of scaling, this can lead to considerable cost savings while achieving the same result. It also results in a clear and organized line layout and prevents the lines from becoming entangled if the receiving body rotates. With only one line, rotation can be maintained using a sliding coupling.

[0025] In a special design, the positive pressure line and the negative pressure line can be routed to the groove profile and the receiving roller from different sides. This allows the lines to be neatly routed without any possible kinks or crossings.

[0026] Advantageously, the vacuum and pressure lines can be sealed on one side. This allows for a significant reduction in the amount of pressure lines required, without compromising functionality. 322028-EP-PCT / 29.07.2025 / nc / mw

[0027] - 6 - In a further embodiment, the receiving roller can have exhaust and intake openings, which can be arranged individually or in groups alternately in a linear pattern along the longitudinal direction of the receiving roller. This is advantageous for generating the Coanda effect, which creates an additional suction effect that causes the top layer of the flexible material to flutter, thereby ensuring optimized adhesion of the layer to the receiving roller. Because the openings are in a line but connected to different pressure and vacuum lines, it is easy to arrange the specified angle differently. While the intake should be essentially perpendicular to the surface of the receiving body, the exhaust direction is essentially transverse to it; in practice, this will be an obtuse angle.

[0028] In a specific embodiment, the receiving roller can be equipped with at least one movable clamping finger to hold the single, flexible layer of material that has been suctioned in. This allows the suctioned layer to be held firmly and secured during transport.

[0029] Furthermore, it appears advantageous if the clamping finger is equipped with at least one transmitted light sensor and / or a tactile sensor to determine the number of layers picked up. By measuring the intensity of the transmitted light, the gripping device can obtain information about the thickness of the picked-up layer in a cost-effective manner. Pre-calibration allows the gripping device to quickly and precisely evaluate how many layers are actually on the roll and, if necessary, adjust its position without further checks if too many have been picked up.

[0030] The invention described above will be explained in more detail below using an exemplary embodiment.

[0031] It shows 322028-EP-PCT / 29.07.2025 / nc / mw

[0032] Fig. 1 shows a receiving body in the form of a receiving roller, which rolls on a surface provided for receiving, in a side cross-sectional view.

[0033] Fig. 2 shows the receiving roller according to Figure 1 after a further rotation and suction of a single layer in a lateral cross-sectional view,

[0034] Fig. 3 shows the receiving roller according to Figure 1 during singulation using the Coanda effect in a side cross-sectional view,

[0035] Fig. 4 shows the receiving roller according to Figure 1 after singulation with attached clamping finger and singulation test with a transmitted light sensor, as well as

[0036] Fig. 5 shows the receiving roller according to Figure 1 in a perspective sectional view with the overpressure and underpressure lines shown within a roller segment.

[0037] Figure 1 schematically shows the first step of a process for gripping a layer 3 to be separated, which consists of a total of four steps. In the first step, a receiving body of the gripping device 1, which is designed as a receiving roller 2, is brought into contact with the flexible material consisting of several layers 7. Several vacuum lines 10, which are connected via short channels to suction openings 4, run longitudinally through the receiving roller 2. The channels are arranged, as shown in detail in Figure 5, such that the suction openings 4 322028-EP-PCT / 29.07.2025 / nc / mw

[0038] - 8 - more or less perpendicularly to the surface 5 of the receiving roller 2, so that the suction is radial.

[0039] Overpressure lines 8 also run within the receiving roller 2, communicating with discharge openings 6. Due to the lateral offset of the overpressure lines 8, the discharge openings 6 are oriented at an angle, preferably an obtuse angle, relative to the direction of airflow and the direction of intake. This results in a more lateral airflow, which runs essentially tangentially to the surface 5 of the receiving roller 2. This is not yet noticeable upon initial contact of the receiving roller 2 with the layers.

[0040] In the second step, as shown in Figure 2, the layer 3 to be separated is already lifted slightly by suction and moved towards the receiving roller.

[0041] 2. It is possible that several layers were lifted simultaneously.

[0042] In the third step, the blowing of compressed air through the blowout openings 6 causes the uppermost layer 3, which is to be separated, to flutter. This results in several lifted layers moving differently due to the varying excitation and then separating at that point. This ensures that only a single layer 3 adheres to the receiving roller 2. This is shown in Figure 3.

[0043] Figure 4 showed in a fourth step how the recorded, isolated layer

[0044] 3 is fixed with a clamping finger 17, whereby a transmitted light sensor 18 integrated in the clamping finger 17 is used to check whether only a single layer 3 has actually been recorded.

[0045] Figure 5 shows the receiving roller 2 in a perspective view. The linearly arranged intake openings 4 and exhaust openings 6, due to their common arrangement in a common line, produce a 322028-EP-PCT / 29.07.2025 / nc / mw

[0046] - 9 -

[0047] Fluttering of the picked-up layer 3 to be separated is caused by the Coanda effect. The dashed lines in a pair of overpressure line 8 and underpressure line 10 show that the channels connecting them to the discharge openings 6 and intake openings 4 are at different angles to the surface 5 of the pickup roller 2. The discharge openings 6, which open very shallowly to the surface 5, are thus elongated, while the radially opening intake openings 4 are round. The angles of the airflows support the desired Coanda effect and ensure reliable separation.

[0048] The receiving roller 2 consists of a total of four roller segments 12, which have linearly arranged intake openings 4 and exhaust openings 6 and are held together by a groove profile 13. The entire receiving roller 2 can be moved radially by rotating the groove profile 14. Fastening elements 15 of the roller segments 12 are inserted into the undercut grooves 14 of the groove profile 13, ensuring secure mounting. At the same time, the use of a groove profile 13 represents an exceptionally economical, easy-to-manufacture, and robust design. The individual roller segments 12 are identical to each other and are rotated only by 90° relative to each other. A pressure distributor (not shown here) can be installed on both sides to connect a common overpressure line to all corresponding lines within the roller segments 12. The vacuum line can be operated in the same way.The end of the roller segment 12 opposite the respective pressure line can be sealed so that the pressure does not drop opposite.

[0049] The above description describes a gripping device which, using simple means, is capable of reliably separating layers of flexible material to be separated. 322028-EP-PCT / 29.07.2025 / nc / mw

[0050] - 10 -

[0051] REFERENCE MARK LIST

[0052] 1 Gripping device 2 Receiving roller

[0053] 3 isolated locations

[0054] 4 Intake opening

[0055] 5 Surface of the receiving roller

[0056] 6 exhaust openings 7 layers

[0057] 8 Overpressure line

[0058] 10 Vacuum line

[0059] 12 roller segment

[0060] 13 Groove profile 14 Grooves

[0061] 15 Fasteners

[0062] 16 pinching fingers

[0063] 17 Transmittance sensor

Claims

322028-EP-PCT / 29.07.2025 / nc / mw - 11 - PATENT CLAIMS 1. Gripping device (1) comprising a receiving body for separating and receiving layers (3) of a flexible material to be separated, wherein the receiving body is assigned at least one radially oriented suction opening (4) for the adhesion of the layers (3) to be separated, wherein the receiving body is assigned at least one substantially tangentially oriented discharge opening (6) to a surface of the receiving body for separating individual layers (7) of flexible materials, wherein the at least one discharge opening (6) is connected to at least one overpressure line (8) and the at least one suction opening (4) is connected to at least one underpressure line (10), wherein the overpressure line (8) and the underpressure line (10) traverse the receiving body at least section by section in the longitudinal direction, characterized in that the receiving body is designed as a radially movable receiving roller (2).

2. Gripping device according to claim 1, characterized in that the receiving roller (2) has an elliptical, in particular round, cross-section.

3. Gripping device according to one of claims 1 or 2, characterized in that the receiving roller (2) is divided into at least two, preferably four, roller segments (13), wherein at least one roller segment (13) is assigned an overpressure line (8) and a vacuum line (10). 322028-EP-PCT / 29.07.2025 / nc / mw - 12 - 4. Gripping device according to claim 3, characterized in that the roller segments (13) are made of a plastic or are provided with a plastic coating.

5. Gripping device according to claim 3 or 4, characterized in that the roller segments (13) are arranged around a groove profile (14) with undercut grooves (15), wherein the roller segments (13) each have fastening means (16) which are received in the undercut grooves (15) of the groove profile (14).

6. Gripping device according to claim 5, characterized in that at least one drive (19) is assigned to the end of the groove profile (14) which rotates the receiving roller (2) about a longitudinal axis (20).

7. Gripping device according to one of claims 3 to 6, characterized in that the overpressure line (8) and the underpressure line (10) of a roller segment (13) are connected to a pressure distributor.

8. Gripping device according to one of the preceding claims, characterized in that the overpressure line (8) and the underpressure line (10) are guided along the groove profile (14).

9. Gripping device according to one of claims 7 and 8, characterized in that the overpressure line (8) and the underpressure line (10) are closed on one side.

10. Gripping device according to one of the preceding claims, characterized in that the receiving body has blow-out openings (6) and suction openings (4) which are arranged individually or in groups alternately in a linear fashion in the longitudinal direction (16) of the receiving body. 322028-EP-PCT / 29.07.2025 / nc / mw - 13 - 11. Gripping device according to one of the preceding claims, characterized in that the receiving body is assigned at least one movable clamping finger (17) for holding exactly one suctioned flexible material layer (3).

12. Gripping device according to claim 11, characterized in that the clamping finger (17) is assigned at least one transmitted light sensor (18) and / or a tactile sensor for determining the number of suctioned layers (3).

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