DEVICE AND METHOD FOR TRANSPORTING AND SEPARATING BLANKS FROM A MATERIAL WEB

Abstract

The invention relates to a device (100) for transporting and separating blanks (1010) from a material web (1000), comprising a vacuum cylinder (8) for transporting the blanks (1010), a vacuum transport cylinder (7) for further transporting the blanks (1010), and a control unit (9). According to the invention, the vacuum cylinder (8) has a pivotable vacuum segment (82) and a rotary actuator (85) is provided for rotating the vacuum segment during operation. This makes it possible to reduce the effective vacuum region on a surface of the vacuum cylinder (8). The invention also relates to a method for transporting and separating blanks from a material web. A device and method enable a gentler and more accurate transfer of blanks from a vacuum cylinder to a vacuum transport cylinder.

Claims

1. A device for transporting and separating blanks from a material web, comprising a vacuum cylinder for transporting the blanks, a vacuum transport cylinder arranged downstream thereof for further transporting the blanks, with a further downstream transfer level (E) for taking over the blanks from the vacuum transport cylinder, and with a control unit, characterized in that the vacuum cylinder has a pivotable vacuum segment which extends over an angular range of the vacuum cylinder for applying vacuum to the surface of the vacuum cylinder, and that a rotary actuator is provided for rotating the vacuum segment, wherein the rotary actuator is connected to the control unit by means of data transmission technology.

2. The device according to claim 1, wherein at least one movement profile for the rotary actuator is stored in the control unit.

3. The device according to claim 1, wherein the pivot axis of the vacuum segment lies in the axis of rotation of the vacuum cylinder.

4. The device according to claim 3, wherein the vacuum segment extends over an angular range of 180-300 of the vacuum cylinder, in particular from 250-290.

5. The device according to claim 1, wherein the vacuum segment is formed by a sector which is open toward the outer surface of the vacuum cylinder and is rotatably mounted within the vacuum cylinder, or that the vacuum cylinder has supply channels distributed evenly around its circumference and the vacuum segment is formed by at least one control disc which can connect the supply channels to a vacuum system.

6. The device according to claim 1, wherein at least the vacuum cylinder is equipped with a controllable rotary drive.

7. The device according to claim 1, wherein the device is equipped with: a material web feeding mechanism for transporting a material web, and/or a punching cylinder and a counter-punching cylinder for punching blanks from the material web upstream of the vacuum cylinder and/or the vacuum transport cylinder, and/or a vacuum transport cylinder with an adhesion-optimized surface, and/or if the material web is multi-layered, with at least one carrier layer and a product layer, with a delamination unit for separating the blanks from the carrier layer, and/or a mechanism for removing the punching residues and, if necessary, the carrier layer, and/or a conveyor belt or a conveyor system with product receptacles in the transfer level (E) for further conveying the blanks or, with a product web in the transfer level (E) for receiving the blanks.

8. A method for transporting and separating blanks from a material web, comprising the following steps: a) feeding a material web with blanks, b) transporting the blanks on a vacuum cylinder, c) transferring the blanks to a vacuum transport cylinder, and d) transporting the blanks on the vacuum transport cylinder, e) transferring the blanks to a transfer level (E), wherein, in step c), the effective vacuum region on a surface of the vacuum cylinder is reduced during the transfer of a respective blank.

9. The method according to claim 8, wherein the vacuum cylinder has a vacuum segment which extends over an angular range of the vacuum cylinder for applying vacuum to its outer surface, and the vacuum segment is pivoted in step c) against the direction of rotation (R) of the vacuum cylinder.

10. The method according to claim 9, wherein the vacuum segment starts to rotate against the direction of rotation (R) as soon as at least 20%, in particular at least 40%, of the area of a respective blank has been transferred from the vacuum cylinder to the vacuum transport cylinder and is held by the latter.

11. The method according to claim 9, wherein the vacuum segment is pivoted in the direction of rotation (R) of the vacuum cylinder before a respective subsequent next blank is transferred from the vacuum cylinder to the vacuum transport cylinder.

12. The method according to claim 8, wherein in step c), during the start of the transfer of a respective blank from the vacuum cylinder to the vacuum transport cylinder, the vacuum cylinders rotate synchronously with the vacuum transport cylinder.

13. The method according to claim 8, wherein the vacuum transport cylinder is moved at a constant rotational speed (R).

Description

EXEMPLARY EMBODIMENT

[0051] The invention will be explained in more detail with reference to the accompanying figures. Corresponding elements and components are marked with the same reference symbols in the figures. For the sake of clarity, the figures are not shown to scale.

[0052] The following diagram shows

[0053] FIG. 1 a first embodiment of a device for transporting and separating blanks

[0054] FIGS. 2a and b a second embodiment of a device for transporting and separating blanks of a single-layer material web with two sub-variants

[0055] FIG. 3 a third embodiment of a device for transporting and separating blanks from a multi-layer material web

[0056] FIG. 4 a,b,c a detailed view of the vacuum cylinder and the vacuum transport cylinder at different points in time

[0057] FIG. 5 a blank in a top view

[0058] FIG. 6 a,b two embodiments of a vacuum segment.

[0059] FIG. 1 shows a first embodiment of a device 100 for transporting a material web 1000 consisting of blanks 1010 arranged in a row and serves to separate the blanks 1010. The device 100 is equipped with a material web feeding mechanism 1 for transporting the material web 1000, a vacuum cylinder 8 for transporting the blanks 1010, a vacuum transport cylinder 7 arranged downstream thereof (as viewed in the transport direction T) for further transporting the blanks 1010, and a transfer level E further downstream for taking over the blanks 1010 from the vacuum transport cylinder 7. Only individual blanks 1010 are shown as examples in the figures.

[0060] In transfer level E, a product web 2000 is guided and transported to receive the blanks 1010 from the vacuum transport cylinder 7.

[0061] FIGS. 2a and b show a second embodiment of a device for transporting and separating blanks from a single-layer material web 1000 in two variants a) and b).

[0062] The device 100 is equipped with a punching cylinder 2 and a counter-punching cylinder 3 for punching blanks 1010 from the material web 1000, which are arranged upstream of the vacuum transport cylinder 7. The vacuum cylinder 8 is formed by the counter-punching cylinder 3 in variant a) and by the punching cylinder 2 in variant b) and has its own independent drive motor (not shown). For clarity, a material web feeding mechanism 1 is not shown here or in the figure below. Downstream of the punching cylinder 2, a mechanism 5 is arranged for removing the punching residues 1020.

[0063] In transfer level E, a product web 2000 is guided and transported to receive the blanks 1010 from the vacuum transport cylinder 7.

[0064] FIG. 3 shows a third embodiment of a device 100 for transporting and separating blanks, which is similar in design to the device 100 shown in FIG. 2. In contrast, the material web 1000 is multi-layered with at least one carrier layer 1030 and one product layer 1040. Downstream of the punching cylinder 2, the device has a delamination unit 4 for separating the blanks 1010 from the carrier layer 1030.

[0065] Furthermore, a mechanism 5 is provided for removing the punching residues 1020 and the carrier layer 1030.

[0066] In further contrast to the embodiments described above, the transfer level E has a conveyor belt 6 for further transporting the blanks 1010.

[0067] FIGS. 4a-c show a detailed view of the vacuum cylinder and the vacuum transport cylinder over time.

[0068] Vacuum cylinder 8 and vacuum transport cylinder 7 can each be equipped with their own independent drive motor 84, so that vacuum cylinder 8 can be rotated with a speed profile with different rotational speeds R.

[0069] The vacuum cylinder 8 has an adjustable vacuum segment 82, by means of which the outer surface of the vacuum cylinder 8 is subjected to vacuum. The vacuum segment 82 is fluidically connected to a vacuum generator 83.

[0070] As indicated by the double arrows, the vacuum segment 82 can be pivoted in its position, i.e., rotated, but is not enlarged or reduced in size. The pivot movement is performed by a rotary actuator 85 controlled by the control unit 9.

[0071] Part of the device 100 is also a control unit 9, with which at least the drive motor 84 of the vacuum cylinder 8 and the rotary actuator 85 are connected by data transmission technology and can be controlled. Speed profiles for the rotation of the vacuum cylinder 8 and movement profiles for the rotating of the vacuum segment 82 are stored or can be generated in the control unit 9, which are dependent on the length 1013 and/or the area distribution over the length 1013 of a respective blank 1010. The movement profile imposed on the rotary actuator 85 also depends on the speed profile of the vacuum cylinder 8.

[0072] The vacuum segment 82 shown in the snapshot in FIG. 4a is in a non-deflected normal position. The blank 1010, which has just been transferred with its front edge 1014 to the vacuum transport cylinder 8, is held by vacuum on the vacuum cylinder 8 by the rolling gap over its entire length up to its rear edge 1012. This ensures that the blank 1010 can be transferred from the vacuum cylinder 8 to the vacuum transport cylinder 7 with positional accuracy.

[0073] FIG. 4b is a snapshot taken a little later. Vacuum cylinder 8 and vacuum transport cylinder 7 continued to rotate, transporting blank 1010 further. In order to reduce the effective vacuum area of the vacuum cylinder 7 and also reduce the holding force of the vacuum on the blank 1010, the vacuum segment 82 was pivoted against the direction of rotation R of the vacuum cylinder 8, as indicated by the arrows. In the region of the rolling gap between vacuum cylinder 8 and vacuum transport cylinder 7, the outer surface of vacuum cylinder 8 is ventilated and blank 1010 is not subjected to any vacuum-induced holding force here. This reduces the holding force acting on the rear region of the blank 1010, which makes it possible to slow down the vacuum cylinder 8 without causing the blank 1010 to shift during further transfer. Thanks to the speed reduction of the vacuum cylinder 8, which is achieved by applying a corresponding speed profile to the drive motor 84, the distance between two successive blanks 1010 can be increased.

[0074] As can be seen from the next snapshot in FIG. 4c, the distance between the blanks 1010 was increased. To ensure that the subsequent blank 1010 with its front edge 1011 is held securely by the vacuum cylinder 8 at the start of transfer to the vacuum transport cylinder 7, the vacuum segment 82 is swung back by a pivoting movement in the direction of rotation R of the vacuum cylinder 8, as indicated by two arrows. The pivot movement is effected by the rotary actuator 85, controlled by the control unit 9. The pivot movement can have the same rotational speed as the vacuum cylinder 8. The vacuum segment 82 is pivoted until it returns to its normal position (see FIG. 4a).

[0075] The movement sequence of vacuum segment 82 and vacuum cylinder 8, as outlined in FIGS. 4a-c, is repeated for each blank 1010.

[0076] The vacuum transport cylinder 7 is equipped with an adhesion-optimized surface 81 to improve the adhesion of the blanks 1010 and reduce slippage during transfer between the cylinders 7, 8.

[0077] FIG. 5 shows a blank 1010 in a top view with the dimensions of the blank 1010.

[0078] From the front edge 1011 to the rear edge 1012, a blank has a length 1013. The blank 1010 has a width of 1015. The area of the blank, as the product of length 1013 and width 1015, is marked with 1016. A subarea 1014, which occupies of the front region of the blank 1010, i.e., more than 30% of its total area, is hatched for clarification.

[0079] FIGS. 6 a and b show two embodiments of a vacuum segment. In the embodiment shown in FIG. 6a, the vacuum segment 82 is formed by a hollow cylinder, a sector, which is open on one side on its outer surface and is rotatably mounted inside the vacuum cylinder 8. Where the hollow cylinder is open on its outer surface, a vacuum is provided on the outer surface of the vacuum cylinder 8. Where the hollow cylinder is closed on its outer surface, no vacuum is provided on the outer surface of the vacuum cylinder 8 and there is a region 86 without vacuum. The hollow cylinder can contain a chamber which is connected via a rotary feedthrough (not shown) in the rotational axis A of the vacuum cylinder 8 to a vacuum system and thus supplies boreholes or holes or pores in the jacket surface of the vacuum cylinder 8 with vacuum.

[0080] In the embodiment shown in FIG. 6b, the vacuum segment 82 is formed by a pivotable control disc, which is a connecting link between the vacuum cylinder 8 and a fixed disc 87 with a vacuum connection. The vacuum cylinder 8 is provided with supply channels running axially and evenly distributed around its circumference, which are indicated by a dotted line and which have a fluid connection to holes or pores in the outer surface of the vacuum cylinder 8. The control disc is used to connect the supply channels to a vacuum system.

[0081] The control disc closes or opens the supply channels. The control disc can be designed so that it has kidney-shaped recesses on its inner side (shown on the left in the illustration), which are connected to a vacuum system on the outer side (shown on the right in the illustration). The control disc with its vacuum-pressurized kidney is mounted so that it can pivot around the common axis A with the vacuum cylinder 8 and can be adjusted from the outside using a rotary actuator 85.

REFERENCE LIST

[0082] 1 material web feeding mechanism [0083] 2 punching cylinders [0084] 3 counter-punching cylinders [0085] 4 delaminating unit [0086] 5 removal mechanism [0087] 6 conveyor belt [0088] 7 vacuum transport cylinders [0089] 8 vacuum cylinders [0090] 81 surface vacuum (transport) cylinder [0091] 82 pivotable vacuum segment (angular range) [0092] 83 underpressure system/vacuum pump [0093] 84 drive motor [0094] 85 rotary actuator [0095] 86 region without vacuum [0096] 87 fixed disc with vacuum connection [0097] 9 control unit [0098] 100 device for transporting and separating [0099] 1000 material web [0100] 1010 blank from material web [0101] 1011 front edge of the blank [0102] 1012 rear edge of the blank [0103] 1013 length of the blank [0104] 1014 of the area of the blank [0105] 1015 width of the blank [0106] 1016 area of the blank [0107] 1020 punching residues [0108] 1030 carrier layer [0109] 1040 product layer [0110] 2000 product web [0111] A rotation axis [0112] E transfer level [0113] R rotation direction [0114] E transfer level