SUCTION GRIPPING DEVICE AND METHOD FOR RECEIVING AND STORING FLAT FLEXIBLE SUBSTRATES

Abstract

A suction gripping device for picking up a plurality of substrates which are flat and flexible includes: a base body, which defines a plane; at least one gas suction vacuum module which is arranged on the base body and has at least one gas suction opening configured for withdrawing gas by suction and for generating a first vacuum so as to suction a respective one of the plurality of substrates against the suction gripping device; and at least one gas ejection vacuum module which is arranged on the base body and has a gas ejection opening configured for ejecting gas and for generating a second vacuum so as to suction the respective one of the plurality of substrates against the suction gripping device.

Claims

1. A suction gripping device for picking up a plurality of substrates which are flat and flexible, the suction gripping device comprising: a base body, which defines a plane; at least one gas suction vacuum module which is arranged on the base body and has at least one gas suction opening configured for withdrawing gas by suction and for generating a first vacuum so as to suction a respective one of the plurality of substrates against the suction gripping device; and at least one gas ejection vacuum module which is arranged on the base body and has a gas ejection opening configured for ejecting gas and for generating a second vacuum so as to suction the respective one of the plurality of substrates against the suction gripping device.

2. The suction gripping device according to claim 1, wherein at least one of: (a) the at least one gas suction vacuum module at least one of (i) forms or includes a Venturi ejector and (ii) includes the following: a gas inlet, a gas outlet, a first connection which runs from the gas inlet to the gas outlet and which has a constriction, and a second connection which branches off between the gas inlet and the gas outlet to the at least one gas suction opening so as to generate the first vacuum by way of a Venturi effect; and (b) the at least one gas ejection vacuum module at least one of (i) forms or includes a Bernoulli floating suction cup and (ii) includes the following: a gas inlet and a connection from the gas inlet to the gas ejection opening, wherein the gas ejection opening is configured such that an ejected gas runs at an angle to the plane of the base body so as to generate the second vacuum by means of a Bernoulli effect.

3. The suction gripping device according to claim 1, wherein the at least one gas suction vacuum module includes a contact surface configured for contactingat least in a plurality of regions of the contact surfacethe respective one of the plurality of substrates that is to be picked up by the suction gripping device, wherein the at least one gas suction opening forms a recess within the contact surface, and wherein the suction gripping device includes a plurality of the at least one gas suction opening each forming a respective one of the recess.

4. The suction gripping device according to claim 3, wherein at least one of: (a) the suction gripping device includes a plurality of the at least one gas suction vacuum module; (b) the suction gripping device includes a plurality of the at least one gas ejection vacuum modules; (c) the at least one gas suction vacuum module is arranged closer to a center of the plane of the base body than the at least one gas ejection vacuum module; (d) the suction gripping device includes a plurality of the at least one gas ejection vacuum module, and the at least one gas suction vacuum module is arranged between the plurality of the at least one gas ejection vacuum module.

5. The suction gripping device according to claim 3, wherein the suction gripping device includes at least one gas suction vacuum module group and two gas ejection vacuum module groups, the at least one gas suction vacuum module group being arranged in a first direction between the two gas ejection vacuum module groups, wherein the at least one gas suction vacuum module group includes at least one of the at least one gas suction vacuum module, the contact surface of which extends in a second direction running perpendicular to the first direction, and wherein each of the two gas ejection vacuum module groups includes a plurality of the at least one gas ejection vacuum module which are arranged side-by-side in the second direction running perpendicular to the first direction.

6. The suction gripping device according to claim 5, wherein the base body includes opposing edges, the two gas ejection vacuum module groups being arranged at the opposing edges of the base body.

7. The suction gripping device according to claim 3, wherein the at least one gas suction vacuum module defines a first suction direction, and wherein the at least one gas ejection vacuum module defines a second suction direction which runs at an angle to the first suction direction.

8. The suction gripping device according to claim 3, wherein the suction gripping device includes at least four of the at least one gas ejection vacuum module, wherein the at least one gas suction vacuum module is arranged both in a first direction and in a second direction running perpendicular to the first direction between the at least four of the at least one gas ejection vacuum module, and wherein the at least one gas suction vacuum module is arranged within a quadrilateral defined by the at least four of the at least one gas ejection vacuum module.

9. The suction gripping device according to claim 3, wherein at least one of: (a) the at least one gas suction vacuum module defines a first suction direction and the at least one gas ejection vacuum module defines a second suction direction, wherein the first suction direction and the second suction direction run parallel to one another; and (b) the at least one gas ejection vacuum module is set back at least one of in the first suction direction, in the second suction direction, perpendicular to the contact surface of the at least one gas suction vacuum module, and perpendicular to the plane of the base body.

10. The suction gripping device according to claim 3, wherein at least one of: (a) the at least one gas suction vacuum module and the at least one gas ejection vacuum module each form respectively an independent component; (b) the suction gripping device includes a distance of at least 1 centimeter between the at least one gas suction vacuum module and the at least one gas ejection vacuum module; and (c) the at least one gas suction vacuum module and the at least one gas ejection vacuum module are activatable separately.

11. The suction gripping device according to claim 1, wherein at least one of: (a) the at least one gas suction vacuum module includes a holding force of at least 12 newtons; (b) the at least one gas ejection vacuum module includes a holding force of at least 1.8 newtons; and (c) at least one of (i) the at least one gas suction vacuum module is variably activatable so as to effect at least two different values of the holding force of the at least one gas suction vacuum module, and (ii) the at least one gas ejection vacuum module is variably activatable so as to effect at least two different values of the holding force of the at least one gas ejection vacuum module.

12. The suction gripping device according to claim 1, wherein the plurality of substrates include at least one of (a) a plurality of thin flexible glass panes and (b) a plurality of thin flexible paper sheets, the plurality of thin flexible glass panes and the plurality of thin flexible paper sheets each including a thickness of less than 100 ?m.

13. A method for picking up a plurality of substrates which are flat and flexible, the method comprising the steps of: using a suction gripping device including at least one gas suction vacuum module and at least one gas ejection vacuum module; moving the suction gripping device closer to a respective one of the plurality of substrates which is flat and flexible; and picking up the respective one of the plurality of substrates by way of the suction gripping device, the respective one of the plurality of substrates being suctioned by way of the at least one gas suction vacuum module and by way of the at least one gas ejection vacuum module with a time offset.

14. The method according to claim 13, wherein the suction gripping device further includes a base body which defines a plane, wherein the at least one gas suction vacuum module is arranged on the base body and has at least one gas suction opening configured for withdrawing gas by suction and for generating a first vacuum so as to suction a respective one of the plurality of substrates against the suction gripping device, and wherein the at least one gas ejection vacuum module is arranged on the base body and has a gas ejection opening configured for ejecting gas and for generating a second vacuum so as to suction the respective one of the plurality of substrates against the suction gripping device.

15. The method according to claim 13, the method further comprising at least one of the following steps: picking up an air-impermeable substrate of the plurality of substrates by way of the suction gripping device, wherein the air-impermeable substrate is first suctioned by way of the at least one gas suction vacuum module and is then picked up completely by way of the at least one gas ejection vacuum module; and picking up an air-permeable substrate of the plurality of substrates by way of the suction gripping device, wherein air is first blown through the air-permeable substrate, and the air-permeable substrate is lifted by way of the at least one gas ejection vacuum module, and then the air-permeable substrate is picked up completely by way of the at least one gas suction vacuum module.

16. The method according to claim 13, the method further comprising the step of releasing the respective one of the plurality of substrates from the suction gripping device by terminating suctioning by way of at least one of the at least one gas suction vacuum module and the at least one gas ejection vacuum module.

17. The method according to claim 16, wherein an air-impermeable substrate of the plurality of substrates is blown off the suction gripping device by way of the at least one gas suction vacuum module.

18. The method according to claim 13, further comprising at least one of the following steps: successively lifting a plurality of air-impermeable substrates of the plurality of substrates and a plurality of air-permeable substrates of the plurality of substrates from a stack (S) of the plurality of air-impermeable substrates and the plurality of air-permeable substrates, wherein both the air-impermeable substrates and the air-permeable substrates are lifted from the stack by a same one of the suction gripping device; and successively placing a plurality of air-impermeable substrates of the plurality of substrates and a plurality of air-permeable substrates of the plurality of substrates one on top of another to form a stack of the plurality air-impermeable substrates and the plurality of air-permeable substrates, wherein both the plurality of air-impermeable substrates and the plurality of air-permeable substrates are placed on the stack by a same one of the suction gripping device.

19. A stack (S) of a plurality of substrates, the stack comprising: the plurality of substrates, which include a plurality of air-impermeable substrates and a plurality of air-permeable substrates, at least one of (a) the air-impermeable substrates having a thickness of less than 70 ?m, and (b) the plurality of air-permeable substrates having a thickness of less than 80 ?m.

20. The stack according to claim 19, wherein at least one of: (a) the stack includes at least 50 ones of the plurality of air-impermeable substrates; (b) at least one of the plurality of air-permeable substrates is arranged between each of the plurality of air-impermeable substrates; (c) the plurality of air-permeable substrates protrude laterally beyond the plurality of air-impermeable substrates; and (d) the plurality of air-permeable substrates each including a first surface and a second surface opposite the first surface, the first surface including a first surface roughness, the second surface including a second surface roughness which is different from the first surface roughness.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0059] FIG. 1 is a three-dimensional view of a suction gripping device configured to pick up raw glass substrates;

[0060] FIG. 2 is a view of the underside of the suction gripping device of FIG. 1;

[0061] FIG. 3 is a sectional side view of the suction gripping device of FIG. 1;

[0062] FIG. 4 is a three-dimensional view of a suction gripping device configured to pick up finished glass substrates;

[0063] FIG. 5 is a sectional view of a Bernoulli floating suction cup;

[0064] FIGS. 6A and 6B, wherein FIG. 6A (a top or bottom view) and FIG. 6B (a sectional side view) are views of a raw glass with borders;

[0065] FIGS. 7A and 7B, wherein FIG. 7A (a top or bottom view) and FIG. 7B (a sectional side view) are views of a finished glass without borders;

[0066] FIG. 8 is a side view of a stack of glass substrates and paper sheets;

[0067] FIG. 9 shows a profile over time of the operation of a gas suction vacuum module and of a gas ejection vacuum module as well as the Z-position of the suction gripping device when picking up an air-impermeable substrate (e.g. glass); and

[0068] FIG. 10 shows a profile over time of the operation of a gas suction vacuum module and of a gas ejection vacuum module as well as the Z-position of the suction gripping device when picking up an air-permeable substrate (e.g. paper).

[0069] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one embodiment of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0070] FIGS. 1-3 show a suction gripping device 10 which is configured in particular to pick up flat flexible substrates 1 having opposite borders 2, as shown in FIGS. 6A and 6B. Such substrates 1 having opposite borders are, for example, raw glass substrates. Because of the opposite borders 2, the substrates 1 have a concave surface, in particular when a large number of such substrates are stacked horizontally one on top of another. In the case of two opposite borders 2 which run in a direction R2, the substrates form a concave shape, for example in a direction R1 perpendicular thereto.

[0071] The suction gripping device 10 includes a base body 20 which defines a plane E. In order to pick up a flat flexible substrate 1 having a concave curvature, or opposite borders 2, the suction gripping device 10 includes a plurality of vacuum module groups 3, 4 in a direction R1 running in the plane E, said vacuum module groups being fastened to the base body 20 in a concave arrangement in the direction R1. More specifically, the vacuum module groups 3, 4 arranged side by side in the direction R1 define suction directions N1, N2 which define normals to a convex surface F. The vacuum module groups 3, 4 have vacuum modules, or suction modules, which are based on different operating principles.

[0072] The outer vacuum module groups 4 arranged opposite one another in the direction R1 are in the form of gas ejection vacuum module groups 4 and each include a plurality of gas ejection vacuum modules 40 which are arranged side-by-side transverse to the direction R1, for example in a direction R2 running perpendicular to the direction R1. The gas ejection vacuum modules 40 each have a gas ejection opening 42 and are in particular in the form of Bernoulli floating suction cups, as shown in FIG. 5 and described in greater detail hereinbelow. The gas ejection vacuum modules 40, which are in the form of Bernoulli suction cup modules, serve in particular for distance compensation in the edge region. In the example shown, the gas ejection vacuum module groups 4 each include a plurality of bars, here two bars, namely in each case an inner bar and an outer bar, wherein the outer bars are set back further in a direction perpendicular to the plane E.

[0073] Between the outer gas ejection vacuum module groups 4 there is arranged a gas suction vacuum module group 3 which includes a plurality of gas suction vacuum modules 30, which in this case are in the form of, or include, Venturi ejectors. The gas suction vacuum modules 30 each have a contact surface 34 which extends in the form of a strip in the direction R2. Within the contact surfaces 34 there is a large number of gas suction openings 32 for the withdrawal of gas by suction in order to suction the substrate 1 against the contact surface 34. The gas suction vacuum modules 30, which are in the form of vacuum gripper modules with flow ejectors, serve in particular to suction or fix the substrate over a large area. In the example shown, the gas suction vacuum module group 3 has in each case a plurality of bars, here four, wherein the bars are arranged at the same height in a direction perpendicular to the plane E. The gas ejection vacuum module groups 4 are at an angle and/or set back in a direction perpendicular to the plane E relative to the gas suction vacuum module group 3.

[0074] The suction gripping device 1 can be used as a suction gripping tool for UTG, in particular for picking up raw glasses with a border, which may in particular also be present in a stack, so that large concave curvatures can sometimes occur. The above-described suction gripping device 10 of convex form can flexibly be used for different glass curvatures. This is because the gas ejection vacuum modules 40 have a high suction effect across a distance and in particular cause the substrate to jump up. In this respect, the gas ejection vacuum modules 40 (e.g. Bernoulli floating suction cups) and the gas suction vacuum modules 30 (e.g. Venturi ejectors) advantageously cooperate in order to cause the substrate to jump up, in particular at its edge, by way of the gas ejection vacuum modules 40 and, in particular thereafter, to fix and/or suction the substrate over a large area by way of the gas suction vacuum modules 30.

[0075] FIG. 4 shows a suction gripping device 10 which is configured in particular to pick up flat flexible substrates 1 having a substantially planar surface as shown in FIGS. 7A and 7B. Such substrates are, for example, finished glass substrates which may have been obtained, for example, from raw glass substrates by removal of the borders.

[0076] The suction gripping device 10 has some aspects in common with the suction gripping device already described above, so that some of the features described above also apply to this embodiment and vice versa. The suction gripping device 10 includes a base body 20 which defines a plane E. In order to pick up a flat flexible substrate 1, the suction gripping device 10 includes vacuum modules 30, 40 which are based on different operating principles.

[0077] The vacuum modules 40 situated on the outside with respect to the plane E of the base body are in the form of gas ejection vacuum modules 40 (e.g. Bernoulli floating suction cups), while the vacuum modules 30 situated on the inside with respect to the plane E of the base body are in the form of gas suction vacuum modules 30 (e.g. Venturi ejectors) having a contact surface 34 and gas suction openings 32 arranged therein.

[0078] The suction gripping device 10 is configured in particular to pick up substrates 1 that lie flat or to pick up substrates 1 with slight warping, in particular for extremely thin materials (e.g. UTG) and/or transparent materials. Accordingly, the suction directions N1, N2 of the vacuum modules 30, 40 run parallel to one another. Because the outer gas ejection vacuum modules 40 have a suction effect over a larger distance, they are set back relative to the gas suction vacuum modules 30 in a direction perpendicular to the plane E. As a result, on the one hand distance compensation in the diagonal of the edge region can take place (Bernoulli suction cup) and on the other hand the substrate can be suctioned over a large area or can be fixed (flat suction cup). For example, the substrate can jump up at its edges and/or corners before the substrate is suctioned in the center.

[0079] FIG. 5 shows in detail a gas ejection vacuum module 40 in the form of a Bernoulli floating suction cup. Each gas ejection vacuum module 40 includes a gas inlet 41 for the admission of compressed air and an annular gas ejection opening 42 through which the compressed air is blown in the form of a cone 44 in the direction toward the substrate 1b. The ejected air flows past the substrate to the outside, so that, as a result of the Bernoulli effect, a vacuum with a suction direction N2 is generated within the gas cone 44.

[0080] The substrate 1b is in this case an air-permeable substrate (e.g. paper), so that the ejected gas flows at least partially through the substrate, which promotes lifting of the substrate 1b, in particular acts to separate the substrate from the underlying layer, in particular in the case of adhesion forces T between the substrate and the underlying layer, which in this case is in the form of an air-impermeable substrate 1a (e.g. glass).

[0081] FIG. 8 shows a stack of air-impermeable substrates 1a (e.g. glass) and air-permeable substrates 1b (e.g. paper) lying horizontally one on top of another. The suction gripping device 10 according to the present invention makes it possible to form such a mixed stack as well as to lift the various substrates from such a stack. A flat substrate 1a, 1b can first be suctioned by way of a gas suction vacuum module 30 and can then be suctioned by way of a gas ejection vacuum module 40 or, conversely, can first be suctioned by way of a gas ejection vacuum module 40 and can then be suctioned by way of a gas suction vacuum module 30. In the case of an air-impermeable substrate 1a, in particular a thin flexible glass pane, the substrate can first be suctioned in the center before it is lifted, or jumps up, at the edge. In the case of an air-permeable substrate 1b, in particular a thin flexible paper sheet, air can first be blown through the substrate, or it can jump up, before the substrate is suctioned and fixed over a large area.

[0082] FIGS. 9 and 10 illustrate, for moving the suction gripping device closer to a substrate, picking up the substrate and releasing the substrate from the suction gripping device, sequences over time of the Z-position (normal to the plane E and/or perpendicular to the directions R1 and R2) of the suction gripping device and operating states of a gas suction vacuum module 30 and of a gas ejection vacuum module 40. The profile over time (s) is shown schematically on the X-axis, and on the one hand the pressure (bar) at the vacuum modules 30, 40 and on the other hand the position of the gripper in the Z-direction (cm) are shown on the Y-axis.

[0083] FIG. 9 illustrates a first example of a sequence, which can be used, for example, in the case of glass. After the suction gripping device has been moved closer to the substrate (s=2), the gas suction vacuum module 30 is first activated (pressure negative) in order to suction the substrate, for example in the middle. Then (s=4), the gas ejection vacuum module 40 is activated (pressure negative) in order to pick up the substrate completely, for example also at the edges. The suction gripping device can then move the picked-up substrate to a different location. In order to release the substrate from the suction gripping device (s=9), suctioning by way of the vacuum modules 30, 40 can be terminated, wherein it can additionally be provided that one of the modules, in particular the gas suction vacuum module 30, blows the substrate off (pressure positive).

[0084] FIG. 10 illustrates a second example of a sequence, which can be used, for example, in the case of paper. After the suction gripping device has been moved closer to the substrate (s=2), the gas ejection vacuum module 40 is first activated (pressure negative) in order to make the substrate jump up, for example at the edges. Then (s=4), the gas suction vacuum module 30 is activated (pressure negative) in order to pick up the substrate completely, for example also in the middle. The suction gripping device can then move the picked-up substrate to a different location. In order to release the substrate from the suction gripping device (s=9), suctioning by way of the vacuum modules 30, 40 can be terminated.

[0085] The combination of gas ejection vacuum modules 40 (e.g. Bernoulli floating suction cups) and gas suction vacuum modules 30 (e.g. Venturi ejectors) is advantageously suitable in particular for separating layers of air-impermeable substrates (e.g. thin flexible glass panes) and air-permeable substrates (e.g. thin flexible paper sheets), which are stacked, for example, horizontally one on top of another, for example alternately. This applies to curved raw glasses as well as to planar finished glasses.

[0086] An air-permeable substrate optionally includes paper or consists of paper, wherein a weight per unit area of between 20 and 80 g/m.sup.2, optionally between 30 and 70 g/m.sup.2, optionally between 40 and 60 g/m.sup.2, for example 50 g/m.sup.2, can be provided. The thickness of an air-permeable substrate can be, for example, between 40 and 100 micrometers, optionally between 50 and 90 micrometers, optionally between 60 and 70 micrometers.

[0087] An air-permeable substrate can further have one or more of the following properties according to DIN EN 1924-2: tensile strength in the machine direction (MD) between 20 and 80 N/15 mm, optionally between 30 and 50 N/15 mm Tensile strength in the cross direction (CD) between 10 and 40 N/15 mm, optionally between 15 and 25 N/15 mm Elongation in the machine direction (MD) between 1.5% and 1.9%, optionally between 1.6% and 1.8%. Elongation in the cross direction (CD) between 1.6% and 2.0%, optionally between 1.7% and 1.9%.

[0088] An air-permeable substrate can additionally have a bursting strength according to DIN EN ISO 2758 of between 90 and 130 kPa, optionally between 100 and 120 kPa, and/or a Cobb value (water) according to DIN EN 20 535 of between 10 and 40 g/m.sup.2, optionally between 15 and 32 g/m.sup.2, and/or an absolute moisture content according to DIN EN 20 287 of between 1% and 5%, optionally between 2% and 4%. An air-permeable substrate in particular has a moisture content of less than 20% (T=35?) and can be stored in a drying cabinet prior to application.

[0089] An air-permeable substrate can further have a pH which is between 5 and 9, optionally between 6 and 8, optionally between 7 and 8, wherein the pH can be determined in particular in accordance with ISO 8791-2.

[0090] An air-permeable substrate can have two opposite surfaces with different surface roughnesses, each of which adjoins, for example, a flat substrate. An option is given to a bottom surface with a higher surface roughness and a top surface with a lower surface roughness. The adhesion of a flat substrate lying beneath an air-permeable substrate on removal of an air-permeable substrate can thus advantageously be reduced, which can be advantageous in particular in the case of thin glasses.

[0091] The roughness of the surfaces of an air-permeable substrate can have the following values according to ISO 8791/4: roughness of the underside between 4 and 14 micrometers, optionally between 6 and 12 micrometers, optionally between 8 and 10 micrometers. Roughness of the bottom surface between 4 and 14 micrometers, optionally between 6 and 12 micrometers, optionally between 8 and 10 micrometers. Roughness of the top surface between 1 and 7 micrometers, optionally between 2 and 6 micrometers, optionally between 3 and 5 micrometers.

[0092] The chemistry of an air-permeable substrate (e.g. paper) is optionally adapted to an air-impermeable substrate (e.g. pH), in particular in order to avoid glass corrosion, leaving a mark and/or haze. In particular, with the air-permeable substrate, the formation of haze can be avoided (glass corrosion, reaction with acids, H.sub.2O+CO.sub.2 can react with Na at a glass surface to give Na.sub.2CO.sub.3 and lead to a salt layer on the surface). The air-permeable substrate is optionally technically chlorine- and acid-free. In particular, it can be avoided with the air-permeable substrate that the acid content and/or chlorine reacts with the surface of the substrate (e.g. glass) to give salts which are difficult to wash off. Moreover, the air-permeable substrate optionally has low particle emission and/or emits particles which can be washed off the air-impermeable substrate.

[0093] The suction gripping devices 10 shown in FIGS. 1-3 and FIG. 4 further optionally have a compensation unit 22 for the direction perpendicular to the plane E and optionally also a valve cluster 55 mounted on the base body 20. The suction gripping devices 10 can further be equipped with a sensor system for vacuum monitoring 50, a sensor system for force monitoring 51 and/or a sensor system for distance monitoring 52 (in particular in the direction perpendicular to the plane E). In order to take appropriate consideration of or to control the special properties of thin glasses (e.g. flexibility, warp, internal stresses, optional borders, horizontal position, intermediate paper, triboelectric effects, etc.), it is particularly advantageous to use flat suction cups in combination with floating suction cups according to the Bernoulli principle and an intelligent sensor system.

[0094] Accordingly, with the present invention, there is provided in particular a gripper for holding and/or moving a flat workpiece, in particular a thin glass. The gripper is suitable for the handling, for the transport, for the separation and joining of air-permeable and non-air-permeable, flexible materials. The gripper is additionally advantageously suitable for the low-contact gripping of substrates.

[0095] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.