GRIPPER ASSEMBLY, APPARATUS FOR RECOVERING A LAYOUT FROM A SHEET MATERIAL AND METHOD FOR SEPARATING A LAYOUT FROM WASTE OF A SHEET MATERIAL

Abstract

A gripper assembly for recovering a layout (22) from a sheet material (12) is presented. It comprises a vacuum gripper (26) with a gripper body (32) on which an array of air flow openings (34a, 34b) is arranged. Air flow openings (34a) associated with one or more blanks (20) of the layout (22) are selectively open and air flow openings (34b) associated to waste (28) of the sheet material (12) are selectively closed. Additionally, an apparatus for recovering a layout (22) from a sheet material (12) comprising such a gripper assembly is described. Furthermore, a method for separating a layout (22) from waste (28) of a sheet material (12) is explained.

Claims

1. A gripper assembly for recovering a layout from a sheet material, the gripper assembly comprising: a conveyor unit for providing the sheet material, wherein the conveyor unit is equipped with a vacuum system for holding the sheet material on the conveyor unit; and a vacuum gripper being adapted for interacting with sheet material provided by the conveyor unit, the vacuum gripper comprising a gripper body on which an array of air flow openings is arranged, each air flow opening being adapted to seize at least a portion of the sheet material by applying a vacuum force thereto, wherein, among the array of air flow openings, air flow openings associated with one or more blanks of the layout are selectively open, and air flow openings associated with waste of the sheet material are selectively closed.

2. The gripper assembly according to claim 1, wherein the array of air flow openings covers a predefined maximum format of the sheet material to be manipulated by the vacuum gripper.

3. The gripper assembly according to claim 1, wherein the array of air flow openings is arranged on a gripping side of the gripper body, wherein the gripping side is equipped with a mask, which selectively covers air flow openings being associated with waste and selectively does not interfere with the air flow openings associated with the one or more blanks of the layout.

4. The gripper assembly according to claim 3, wherein the gripping side of the vacuum gripper is magnetic, and wherein a magnetic cover is attached to the gripping side of the vacuum gripper.

5. The gripper assembly according to claim 4, wherein the mask is positioned between the magnetic side of the vacuum gripper and a magnetic sheet covering the mask on a side opposing the vacuum gripper.

6. The gripper assembly according to claim 1, wherein the conveyor unit further comprises a plurality of suction openings which are fluidically connected to the vacuum system such that the sheet material may be held on the conveyor unit by sucking air through the suction openings by the vacuum system, and wherein a configuration of the suction openings is independent from a size and/or shape of the sheet material to be processed.

7. The gripper assembly according to claim 1, wherein the vacuum system is configured such that a vacuum force applied to the one or more blanks by the vacuum system is smaller than a vacuum force applied to the one or more blanks by the vacuum gripper.

8. An apparatus for recovering a layout from a sheet material, the apparatus comprising: the gripper assembly according claim 1, wherein the sheet material comprising the layout and waste is to be provided by the conveyor unit of the gripper assembly, and wherein the vacuum gripper of the gripper assembly is connected to a manipulation unit, and a layout storage unit on which the one or more blanks of the layout recovered from the sheet material may be positioned.

9. The apparatus according to claim 8, wherein the vacuum gripper includes a plurality of vacuum grippers, each connected to a respective manipulation unit.

10. The apparatus according to claim 9, wherein at least one of the manipulation units comprises an industrial robot, which is adapted to manipulate the respective vacuum gripper within a predefined scope of motion.

11. The apparatus according to claim 8, wherein the layout storage unit is a stacking unit.

12. A method for separating a layout from waste of a sheet material, the method comprising: providing a sheet material on a conveyor unit, wherein the sheet material comprises a layout with one or more blanks and waste, and wherein the sheet material is held on the conveyor unit by a vacuum system of the conveyor unit, seizing the one or more blanks with the vacuum gripper of the gripper assembly according to claim 1, while not interacting with waste, and separating the seized one or more blanks from the waste.

13. The method according to claim 12, further comprising: moving the separated blanks to a blank storage unit.

14. The method according to claim 12, wherein the seizing includes positioning the vacuum gripper over the sheet material, wherein the vacuum gripper selectively seizes the one or more blanks without cooperating with the waste.

Description

[0048] The invention will now be explained with reference to several embodiments which are shown in the attached drawings. In the drawings,

[0049] FIG. 1 shows a schematic representation of an apparatus for recovering a layout from a sheet material according to a first embodiment of the invention, wherein also a sheet material is shown.

[0050] FIG. 2 shows an exemplary sheet material, which may be treated in the apparatus according to FIG. 1,

[0051] FIG. 3 shows a schematic representation of an apparatus for recovering a layout from a sheet material according to a second embodiment of the invention,

[0052] FIG. 4 shows the apparatus according to FIG. 3 seen in a direction IV of FIG. 3,

[0053] FIG. 5 shows a vacuum gripper of a gripper assembly according to the invention while interacting with a sheet material,

[0054] FIG. 6 schematically shows the interaction between the sheet material and a mask of a vacuum gripper and

[0055] FIG. 7 shows a vacuum gripper of a gripper assembly according to a second embodiment of the invention in an exploded representation.

[0056] In FIG. 1 an apparatus 10 for recovering a layout from a sheet material 12 is shown. It cooperates with a sheet material 12 made from paper or cardboard.

[0057] The sheet material 12 is provided on a conveyor unit 14, which is a conveyor belt in the example shown. The conveyor belt moves in a direction indicated by arrow 16.

[0058] The conveyor unit 14 is equipped with a vacuum system 15 for holding the sheet material 12 on an associated surface of the conveyor unit 14.

[0059] To this end the conveyor unit 14 comprises a plurality of suction openings 15a which are fluidically connected to the vacuum system 15 such that the sheet material 12 may be held by sucking air through the suction openings 15a (for better visibility only some of the suction openings 15a are designated by a reference number).

[0060] Furthermore, the apparatus 10 comprises a layout storage unit 18 on which one or more blanks 20 of the layout 22 recovered from the sheet material 12 may be positioned. In the present case, the layout storage unit 18 is a so-called stacking unit. This means that the blanks 20 of the layout 22 are stacked upon each other in the layout storage unit 18.

[0061] Additionally, the apparatus 10 has a manipulation unit 24 to which a vacuum gripper 26 is connected. The manipulation unit 24 and the corresponding vacuum gripper 26 are shown in three different situations designated A, B and C.

[0062] The manipulation unit 24, which is only represented in a schematic way, may comprise an industrial robot, which is adapted to manipulate the respective vacuum gripper 26 within a predefined scope of motion.

[0063] The conveyor unit 14 and the vacuum gripper 26 form a gripper assembly 27.

[0064] A method for separating the layout 22 from waste 28 of the sheet material 12 may be performed by the apparatus 10. In other words a stripping or blanking method is performed.

[0065] An exemplified sheet material 12 comprising a layout 22 with four blanks 20 and waste 28 is represented in FIG. 2.

[0066] In a first step of the method, the sheet material 12 is provided.

[0067] Then, the blanks 20 of the layout 22 are seized with the vacuum gripper 26 (cf. situation A in FIG. 1). In order to do so, the vacuum gripper 26 is positioned over the sheet material 12 and only seizes the layout 22.

[0068] The vacuum gripper 26 does not interact with waste 28.

[0069] After that, as shown in situation B in FIG. 1, the layout 22 is separated from waste 28. In the present case, the layout 22 is lifted by the vacuum gripper 26, whereas waste 28 remains on the conveyor unit 14.

[0070] This is possible since the vacuum system 15 is configured such that a vacuum force applied to the layout 22 by the vacuum system 15 is smaller than a vacuum force applied to the layout 22 by the vacuum gripper 26.

[0071] Subsequently, the vacuum gripper 26 is moved into situation C, where it is positioned over the blank storage unit 18. The blanks 20 are stacked on the blank storage unit 18 or on other blanks 20 already being positioned thereon. Thereafter, the interaction between the vacuum gripper 26 and the blanks 20 is terminated and the vacuum gripper 26 may be moved back to situation A by the manipulation unit 24.

[0072] FIGS. 3 and 4 show a second embodiment of the apparatus 10. This embodiment differs from the embodiment explained above in that it comprises an additional vacuum gripper 26a, which is connected to a respective additional manipulation unit 24a.

[0073] Both vacuum grippers 26, 26a cooperate with one single conveyor unit 14 and one single layout storage unit 18.

[0074] The vacuum grippers 26, 26a may be operated according to two variants. Either both vacuum grippers 26, 26a cooperate with different portions of one single sheet material 12 in a sense that vacuum gripper 26 seizes a first portion of the layout and places it on the layout storage unit 18 and additional vacuum gripper 26a seizes a remaining second portion of the layout and places it on the layout storage unit 18. Alternatively, every second sheet material 12 being provided by the conveyor unit 14 may be treated by the vacuum gripper 26 and every other sheet material 12 by the additional vacuum gripper 26a.

[0075] As shown in FIG. 3, in both variants both vacuum grippers 26, 26a may operate along the same trajectory 30.

[0076] As far as the implementation of the method for separating a layout from waste of a sheet material with the second embodiment is concerned, the above explanations apply in an analogous way.

[0077] In FIGS. 5 to 7 the vacuum gripper 26 is shown in detail. Also an exemplary sheet material 12 is shown. As the additional vacuum gripper 26a is identical, a specific explanation thereof will be omitted.

[0078] The vacuum gripper 26 comprises a gripper body 32. On a gripping side thereof an array of air flow openings 34a, 34b is arranged (for better visibility only some of the air flow openings 34a, 34b are designated by a reference number). Each of the air flow openings 34a, 34b is adapted to seize at least a portion of the sheet material 12.

[0079] As can be seen from FIGS. 5 and 6, only the air flow openings 34a associated with the layout 22, i.e. with one or more blanks 20 of the layout 22, are open. The remaining air flow openings 34b are closed because they are covered with a mask 36. In doing so, the mask 36 does not interfere with the air flow openings 34a associated with the layout 22.

[0080] Consequently, the vacuum gripper 26 is adapted to the geometry of the layout 22 in that in can only seize the blanks 20, when positioned above the sheet material 12. Waste 28 is not gripped by the vacuum gripper 26. Therefore, such a vacuum gripper 26 is well suited for separating a layout 22 from waste 28.

[0081] As can best be seen from FIG. 6, the array of air flow openings 34a, 34b covers a predefined maximum format of sheet material 12 to be manipulated by the vacuum gripper 26.

[0082] The array of air flow openings 34a, 34b is small meshed when compared to the geometry of the layout 22 to be recovered. Therefore, by adapting the mask 36 to the geometry of the layout 22, the vacuum gripper is suitable for recovering a very large variety of different types of layout 22.

[0083] A further embodiment of the vacuum gripper 26 is shown in FIG. 7. In this embodiment, the vacuum gripper 26 is magnetic, more specifically a magnetic cover 38 is attached to the gripping side of the vacuum gripper 26, e.g. by gluing.

[0084] The mask 36 is now positioned between the magnetic cover 38 and a magnetic sheet 40 and thereby securely attached to the vacuum gripper 26.

[0085] The mask 36 is made from non-magnetic material and therefore can be easily exchanged by separating the magnetic sheet 40 from the vacuum gripper 26 and positioning a different mask 36 on the magnetic cover 38.

[0086] As can be seen from the figures, an array of holes is provided both on the magnetic cover 38 and the magnetic sheet 40. These arrays of holes corresponds to the array of air flow openings 34a, 34b. Consequently, neither the magnetic cover 38 nor the magnetic sheet 40 is able to block or obstruct the air flow openings 34a, 34b. Therefore, when adapting the vacuum gripper 26 to a different geometry of the layout 22, it is not necessary to exchange or adapt the magnetic cover 38 or the magnetic sheet 40.

[0087] Apart from these structural differences the functionality of the vacuum gripper 26 according to the second embodiment is not different from the vacuum gripper 26 explained with reference to FIGS. 5 and 6.