Separating and gripping device

Abstract

For certain situations, a gripping device is necessary that is capable of separating layers of flexible materials, then picking them up and processing them. Known gripping devices only have suction openings. If such a suction opening is used, separation becomes more difficult. While it is known to test separation using transmitted light, if this method fails, this knowledge is of no further use. Against this background, the gripping device according to the invention provides a cost-effective way to create a fast and reliable method of separation and subsequent processing by utilizing the Coanda effect. This is achieved by vertical suction followed by blowing out at an obtuse angle, causing the lifted layers of material to flutter and, if several layers have been suctioned, to separate.

Description

[0001] The present invention relates to a gripping device comprising a receiving body for singulating and receiving layers of a flexible material to be singulated, wherein the receiving body is assigned at least one radially oriented suction opening for the adhesion of the layers to be singulated.

[0002] Such a gripping device is already known from WO 2021 / 003141 A1. 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.

[0003] 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 selectively suctioning a single layer of a flexible or sheet material and, after suction, gripping it with a foldable clamping finger to securely hold the single layer. Either the clamping finger or the picking roller has light sources and corresponding light source sensors that generate transmitted light, which is evaluated on the opposite side. Depending on the measured light intensity, it is determined whether exactly a single layer has been gripped.However, the only option after that is to drop the position and try again, unless it is a single situation.

[0004] 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 gripper 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.

[0005] 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.

[0006] 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.

[0007] The invention provides 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 vertically oriented suction opening for the adhesion of the layers to be separated. According to the invention, such a gripping device is characterized in that the receiving body is assigned at least one blow-out opening, oriented substantially tangentially to a surface of the receiving body, for separating individual layers of flexible materials, wherein the at least one blow-out 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 roller at least partially in the longitudinal direction.

[0008] While air is drawn in perpendicularly through the vacuum line across 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.

[0009] 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.

[0010] 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 roll over a layer of material to be received, causing the material to adhere to the receiving body, with a portion of the material layer being removed from the remaining layers simply due to this adhesion and continued rotation.

[0011] 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.

[0012] 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.

[0013] 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.

[0014] In a specific design, it appears advantageous for the roller segments to be 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 allows for easy assembly and also enables quick replacement in the event of a failure, thereby reducing downtime and increasing production throughput. The fastening elements can be, for example, screwed-on or molded T-nuts, or a longitudinally extended insert that can be positively inserted into the groove of the groove profile from the end face.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] Advantageously, the vacuum line and the pressure line can be sealed on one side. This allows for a significant reduction in the amount of pressure lines required, without compromising functionality.

[0019] In a further embodiment, the receiving roller can have exhaust and intake openings, which can be arranged individually or in alternating groups in a linear pattern along the length 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, thus 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 vary the specified angle. While the intake should be essentially perpendicular to the surface of the receiving roller, the exhaust direction is essentially transverse to it; in practice, this will be an obtuse angle.

[0020] 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.

[0021] 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.

[0022] The invention described above will be explained in more detail below using an exemplary embodiment.

[0023] They show Figure 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; Figure 2 shows the receiving roller according to Figure 1 after a further rotation and suction of a single layer in lateral cross-sectional view, Figure 3 the receiving roller according to Figure 1 during singulation using the Coanda effect in a side cross-sectional view, Figure 4, the receiving roller according to Figure 1 after singulation with attached clamping finger and singulation test with a transmitted light sensor, as well as Figure 5 the receiving roller according to Figure 1 in a perspective sectional view with overpressure and underpressure lines drawn within a roller segment.

[0024] Figure 1Figure 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 lengthwise through the receiving roller 2. The channels run as shown in Figure 1. Figure 5 shown in detail, such that the suction openings 4 meet the surface 5 of the receiving roller 2 more or less at right angles, so that the suction is radial.

[0025] 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.

[0026] In the second step, as in Figure 2 As shown, the suction action lifts layer 3, which is to be separated, slightly and pulls it towards the receiving roller 2. It is possible that several layers were lifted simultaneously.

[0027] 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 in Figure 3 shown.

[0028] Figure 4 In a fourth step, it was shown how the recorded, isolated layer 3 is fixed with a clamping finger 17, whereby a transmission sensor 18 integrated in the clamping finger 17 is used to check whether only a single layer 3 has actually been recorded.

[0029] Figure 5Finally, the receiving roller 2 is shown in a perspective view. The linearly arranged intake openings 4 and exhaust openings 6, due to their shared arrangement in a common line, cause the picked-up layer 3, which is to be separated, to flutter due to the Coanda effect. The dashed lines indicate that, in the case of a pair of overpressure line 8 and underpressure line 10, the channels connecting these to the exhaust openings 6 and intake openings 4 are at different angles to the surface 5 of the receiving roller 2. The exhaust 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 that separation is reliably achieved.

[0030] 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.

[0031] The above description thus describes a gripping device which, with simple means, is able to achieve a safe singulation of layers of flexible material to be singulated. REFERENCE MARK LIST

[0032] 1 Gripping device 2 Pick-up roller 3 Isolated layer 4 Suction opening 5 Surface of the pick-up roller 6 Blow-out opening 7 Layers 8 Overpressure line 10 Underpressure line 12 Roller segment 13 Groove profile 14 Grooves 15 Fastening device 16 Clamping finger 17 Transmittance sensor

Claims

1. Gripping device (1) comprising a receiving body for singulating and receiving layers (3) of a flexible material to be singulated, wherein the receiving body is assigned at least one radially oriented suction opening (4) for adhering the layers (3) to be singulated, characterized by the fact that The receiving body is assigned at least one vent opening (6) oriented substantially tangentially to a surface of the receiving body for separating individual layers (7) of flexible materials, wherein the at least one vent opening (6) is connected to at least one overpressure line (8) and the at least one intake 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.

2. Gripping device according to claim 1, characterized by the fact that the receiving body is designed as a radially movable receiving roller (2).

3. Gripping device according to claim 2, characterized by the fact that the receiving roller (2) is elliptical in its cross-section, in particular round.

4. Gripping device according to one of claims 2 or 3, characterized by the fact 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 an underpressure line (10).

5. Gripping device according to claim 4, characterized by the fact that the roller segments (13) are made of plastic or are coated with plastic.

6. Gripping device according to claim 4 or 5, characterized by the fact 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).

7. Gripping device according to claim 6, characterized by the fact thatThe groove profile (14) has at least one drive (19) at its end, which rotates the receiving roller (2) about a longitudinal axis (20).

8. Gripping device according to one of claims 4 to 7, characterized by the fact that the overpressure line (8) and the underpressure line (10) of a roller segment (13) are connected to a pressure distributor.

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

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

11. Gripping device according to one of the preceding claims, characterized by the fact that the receiving body has exhaust openings (6) and intake openings (4) which are arranged individually or in groups alternately in a linear fashion in the longitudinal direction (16) of the receiving body.

12. Gripping device according to one of the preceding claims, characterized by the fact that The receiving body is assigned at least one movable clamping finger (17) for holding exactly one suctioned flexible material layer (3).

13. Gripping device according to claim 12, characterized by the fact 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).

Images