Alignment module for irregular edges

Abstract

The invention relates to an alignment module (11) for a converter (1). The alignment module includes an alignment device (30) having an upper pressing member (22), a lower conveyor (24), and a guide (26). The guide is further provided with a downwardly inclined inlet end (32) configured to guide a lateral portion of the blank underneath the guide while bringing the lateral guide surface (40) into contact with an inner segment edge (S1, S2) of the blank, the inner segment edge is arranged closer to the central longitudinal axis of the blank than a lateral portion of the blank located below the guide.

Description

Technical Field

[0001] The present invention relates to a converting machine for producing paper and cardboard containers, such as folding cartons. In particular, the present invention relates to an alignment module configured to laterally align a blank having irregular lateral edges. Background Art

[0002] Converting machines, such as folding gluing machines, are used in the production of cardboard and cardboard boxes. These machines are configured to receive cut and formed blanks and then fold and glue them to form folding cartons or other similar packaging containers. The blanks are provided with cutting lines that define the overall shape of the blank and crease lines that define the folding positions.

[0003] To ensure that folding occurs at the positions defined by the crease lines, the folding gluing machine includes an alignment module upstream of the folding module. The alignment module is configured to laterally align the blanks. An example of an alignment module is described in document US7398872.

[0004] The alignment module in US7398872 includes an upper pressing member and a lower conveyor configured to receive and convey a blank in a gap therebetween. When the blank is conveyed, one of its lateral edges is pushed against a lateral guide extending along the transport direction of the blank. In this way, the blank is laterally aligned in the converting machine.

[0005] Depending on the geometry of the blank, the alignment module can be configured to align against the left or right side of the blank. Generally, for alignment against a guide, a straight or uniform lateral edge is more advantageous than an irregular lateral edge. However, for some blanks, both their left and right lateral edges are irregular. This type of blank is designed to form quick-lock boxes, wallet-type packages, hand-built boxes, etc. These boxes may also be provided with adhesive strips.

[0006] Therefore, these types of blanks are difficult to align in the transport direction, and there is a risk that the blank rotates during transport in the alignment module. Summary of the Invention

[0007] In view of the prior art, an object of the present invention is to improve the alignment of blanks having irregular lateral edges.

[0008] This object is solved by an alignment module according to claim 1.

[0009] According to a first aspect of the present invention, there is provided an alignment module for a converting machine, the alignment module being configured to correct the lateral position of a blank conveyed through the converting machine along a transport direction. The blank includes a first laterally outer peripheral edge and a second laterally outer peripheral edge, the first laterally outer peripheral edge and the second laterally outer peripheral edge being disposed on opposite sides of a central longitudinal axis of the blank and extending along the transport direction. The alignment module includes at least one alignment device having an upper pressing member, a lower conveyor, and a guide, and wherein the upper pressing member and the lower conveyor are configured to receive and transport the blank in a gap therebetween, and wherein the guide is an elongate rod provided with a lateral guiding surface and extending along the transport direction.

[0010] The guide is further provided with a downwardly inclined inlet end configured to guide a lateral portion of the blank located below the guide while bringing the lateral guiding surface into contact with an inner segment edge of the blank, the inner segment edge being disposed closer to the central longitudinal axis of the blank than the lateral portion of the blank located below the guide. The downwardly inclined inlet end has a wedge shape.

[0011] The first and second laterally outer peripheral edges are irregular and may each include a plurality of segment edges extending along the transport direction and disposed at different lateral positions from the central longitudinal axis of the blank. The term "irregular edge" means an edge that is not straight.

[0012] Each outer peripheral lateral edge includes a distal segment edge and at least one inner segment edge, the inner segment edge being positioned closer to the central longitudinal axis of the blank than the distal segment edge.

[0013] The guide is located laterally of the upper pressing member and the conveyor belt.

[0014] The present invention is based on the recognition that irregular lateral edges include a plurality of different segment edges disposed at different lateral positions. The position and length of some of the inner segment edges are such that they are more conducive to alignment than the segment edges located at the most distal end in the lateral direction (i.e., the distal lateral edge). The lateral direction is defined as perpendicular to the transport direction of the blank. By providing a guide with a downwardly inclined inlet portion (which forces the end of the blank beneath it), the inner lateral segment edges can be accessed by the alignment surface of the guide.

[0015] According to one embodiment, the lower conveyor is positioned such that the lateral portion of the blank is not supported by the lower conveyor.

[0016] In this way, the edge is not supported and is guided downward by gravity beneath the alignment guide.

[0017] In one embodiment, the alignment guide is provided with a groove, and the groove is configured to hold the guiding edge of the blank. The guiding edge is an inner edge in the blank.

[0018] In one embodiment, the alignment module includes an inlet section in which an upper pressing member is arranged at a distance from a lower conveyor, and the downwardly inclined inlet end of the guide is located in the inlet section.

[0019] The alignment guide can be laterally displaceable.

[0020] In one embodiment, the upper alignment module further includes a slider, and the connecting axis of the slider coincides with the connecting axis of the guide rail.

[0021] According to a second aspect of the present invention, there is provided a converting machine including the alignment module according to the first aspect of the present invention, and the converting machine further includes a folding module and a blank rotating module configured to rotate the blank by 90°. The converting machine includes a second alignment module arranged between the blank rotating module and the folding module.

[0022] The blank rotating module and the second alignment module can be separate modules mounted on two separate frames. Alternatively, the blank rotating module and the second alignment module can be a combined module having a single frame. Description of the Drawings

[0023] The present invention will now be described with reference to the drawings, in which like features are denoted by like reference numerals, wherein:

[0024] - Figure 1 is a schematic view of the converting machine in the folding gluing machine configuration;

[0025] - Figure 2a and Figure 2b are respectively a schematic perspective view of a folding box and a plan view of a blank;

[0026] - Figure 3 is a schematic perspective view of the alignment module according to an embodiment of the present invention;

[0027] - Figure 4 is Figure 3 a schematic cross-sectional view of the alignment module and the feeder module in

[0028] - Figure 5a is a detailed plan view of the inlet section of the alignment module according to an embodiment of the present invention;

[0029] - Figure 5b is Figure 5a a cross-sectional view of the inlet section of

[0030] - Figure 6 is a cross-sectional view of an inlet portion of a blank 2; and Figure 5b and;

[0031] - Figure 7 is a top view of a feeder module and an alignment module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] Referring to the accompanying drawings, and in particular Figure 1 , Figure 2a and Figure 2b . The folding gluer 1 is configured to receive a cut and formed blank 2 as shown in Figure 2b , and then fold and glue the blank 2 to form a folding box 2' or other folded and glued packaging container 2'.

[0033] As shown in Figure 1 , the folding gluer 1 of the present invention may include a series of workstations in the form of different modules. From the inlet to the outlet and along the transport direction T, the modules may include: a feeder module 10, an alignment module 11, a folding pre-breaking module 12, a gluing module 14, and a folding module 16. The folding gluer 1 may also include a main user interface 15 and a quality control system 18.

[0034] The alignment module 11 is arranged downstream of the feeder module 10 in the transport direction T and is configured to laterally align the blank 2 to a predetermined lateral position. The predetermined lateral position is defined by the position of the longitudinal crease line 4 and the auxiliary tools and folding positions in the converter 1. Thus, the alignment module 11 is configured to align the blank 2 in a direction perpendicular to the transport direction T.

[0035] An auxiliary module 13 in the form of a strip gluing module and a blank rotating module 17 may be located between the alignment module 11 and the folding pre-breaking module 12. The strip gluing module is configured to apply a strip of glue (i.e., an adhesive line) and a protective cover such that the strip of glue can be used when the box is sealed again after the first use. Such a strip gluing module is provided by Enpro, for example, their "SPA 3.0 - silicone paper applicator". The blank rotating module 17 is configured to rotate the blank 90° before the blank 2 enters the folding module 16. An example of a blank rotating module is described in EP3038954.

[0036] Preferably, a second alignment module 9 is arranged between the blank rotating module 17 and the folding module 16. The blank rotating module 17 and the second alignment module 9 may be separate modules mounted on two separate racks. Alternatively, the blank rotating module 17 and the second alignment module 9 may be a combined module having a single rack.

[0037] After the gluing module 14 and the folding module 16, a conveying module and an adjustment section 21 can be provided to count the shingle flow of the folding carton 2' and separate it into individual batches.

[0038] The converting machine 1 further includes a conveying system 19, which includes conveyors (such as endless belts and rollers) configured to transport the blanks 2 in the transport direction T. The converting machine 1 further includes a central control circuit 20 configured to control the operation of the converting machine 1.

[0039] To enable folding, the blank 2 is provided with crease lines 4. A first set of crease lines 4a extends along the transport direction T of the blank 2 in the alignment module 11. The first set of crease lines 4a also extends along the transport direction T of the blank 2 in the feeder module 10.

[0040] A second set of crease lines 4b is arranged perpendicular to the first set of crease lines 4a. If the blank turning module 17 is used, the second set of crease lines 4b extends along the transport direction T of the blank in the folding module 16.

[0041] The blank 2 has a longitudinal length La in the transport direction T in the alignment module 11. Similarly, if the blank turning module 17 is used, the blank 2 has a longitudinal length Lb in the transport direction T in the folding module 16. For a blank 2 with an irregular leading edge and an irregular trailing edge, the longitudinal lengths La, Lb are the maximum lengths of the blank 2 in the transport direction T.

[0042] In the alignment module 11, the blank 2 is provided with a first outer peripheral side edge 6a and a second outer peripheral side edge 6b. The first outer peripheral side edge 6a and the second outer peripheral side edge 6b can be irregular. The outer peripheral side edges 6a, 6b allow the formation of sheet-like overhangs and folding surfaces.

[0043] The first outer peripheral side edge 6a is provided with a plurality of segment edges S1, which are positioned at different lateral positions relative to the central longitudinal axis C of the blank 2. The central longitudinal axis C is aligned with the transport direction in the alignment module 11. Preferably, the central longitudinal axis C is arranged at the center of the blank 2. Similarly, the second outer peripheral side edge 6b is provided with a plurality of segment edges S2, which are positioned at different lateral positions relative to the central longitudinal axis C of the blank 2. Depending on the type of the packaging container 2' and the shape of the blank 2, the number of the segment edges S1, S2 can be different. The lateral position is defined as the distance along the lateral direction L, and the lateral direction L is defined as the direction perpendicular to the transport direction T of the blank 2 in the alignment module. Therefore, the lateral direction L is also defined as the direction perpendicular to the transport direction T of the blank 2 in the feeder module 10.

[0044] Each outer peripheral side edge 6a, 6b includes a distal segment edge D1, D2 and at least one inner segment edge S1, S2. At least one inner segment edge S1, S2 is positioned closer to the central longitudinal axis C of the blank 2 than the distal segment edges D1, D2. The distal segment edges D1, D2 are located at the lateral ends of the blank 2 in the alignment module 11.

[0045] As Figure 3 shown, the alignment module 11 preferably includes a first alignment device 30a and a second alignment device 30b. The first alignment device 30a is configured to abut against the left side of the blank 2, and the second alignment device 30b is configured to abut against the right side of the blank 2.

[0046] As Figure 5a best shown in, the alignment devices 30a, 30b include an upper pressing member 22, an alignment conveyor 24 and a guide 26. The upper pressing member 22 is provided with a plurality of pressing rollers 23 arranged in a straight line.

[0047] The alignment module 11 is configured to receive the blank 2 in the gap between the upper pressing member 22 and the alignment conveyor 24. The upper pressing member 22 and the alignment conveyor 24 are arranged at an angle along the transport direction T so as to guide the lateral edges 6a, 6b of the blank 2 against the guide 26. The guide 26 is arranged such that its longitudinal extension is aligned with the transport direction T.

[0048] The alignment conveyor 24 includes an endless conveyor belt 25 and is configured to contact the blank 2 and drive the blank 2 forward along the transport direction T. The pressing rollers 23 can rotate freely.

[0049] The first alignment device 30a and the second alignment device 30b are not used simultaneously. Instead, they provide the option of choosing which lateral edge 6a, 6b of the blank 2 to align against the guide 26.

[0050] When one of the alignment devices 30a, 30b is activated, the other is deactivated. In the deactivated alignment device 30a, 30b, the pressing rollers 23 can be moved upward and away from the blank 2 so that the pressing rollers 23 of the deactivated alignment device 30a, 30b do not contact the blank 2.

[0051] As Figure 5a shown, the alignment module 11 may include an entrance portion I. The entrance portion I provides a distance above which the blank 2 is not guided. This can be achieved by arranging at least some of the pressing rollers 23 such that they are arranged at a distance from the alignment conveyor 24. In this way, the pressing member 22 does not grip the blank 2 and the trajectory of the blank 2 in the entrance portion I is not modified by the alignment device 30.

[0052] The length of the inlet section I can be configured such that when the entire longitudinal length La of the blank 2 is located in the alignment module 11, the blank 2 is only moved laterally. This allows the alignment module 11 to receive the entire longitudinal length La of the blank 2 before laterally moving the blank 2. This also allows the blanks 2 to exit the feeder module 10 before changing their trajectory.

[0053] The alignment side is selected based on the geometry of the outer peripheral lateral edges 6a, 6b of the blank 2. The operator can manually select the choice between right and left alignment by inspecting the first outer peripheral lateral edge 6a and the second outer peripheral lateral edge 6b. Alternatively, the control unit 50 can perform calculations to determine which outer peripheral lateral edges 6a, 6b are most suitable for alignment.

[0054] Ideally, the long and straight distal section edges D1, D2 are selected as the suitable alignment edges. However, as Figure 2b shown for the blanks, some blanks 2 have irregular outer peripheral lateral edges 6a, 6b and the distal section edges D1, D2 are relatively short in the transport direction T. For irregular outer peripheral lateral edges 6a, 6b, this alignment device 11 also allows alignment against the inner section edges S1, S2. This is advantageous when there are (in the transport direction T) straight inner section edges S1, S2 that are arranged in the alignment module 11 in the direction of the transport direction T with a significant length. Preferably, the significant length is approximately 50% of the longitudinal length La.

[0055] As Figure 5a and Figure 5b best shown, the guide 26 is provided with an inlet end 32, an outlet end 34 and a longitudinal guide portion 36. The inlet end 32 slopes downward in the transport direction T. The guide 26 has an upper surface 37 and a lower surface 39. The upper surface 37 and the lower surface 39 preferably have an extension that coincides with the horizontal direction H, and the upper surface is arranged vertically above the lower surface in the vertical direction V. In the inlet section I, the upper surface 37 of the guide 26 extends further upstream in the transport direction T compared to the lower surface 39 of the guide 26. In this way, the guide 26 is provided with a downwardly sloping inlet end 32 of the guide 26, which is configured to guide the lateral portion E0 of the blank below the guide 26.

[0056] The inclination angle α can be 20° to 40°, preferably about 30°, with respect to the longitudinal extension of the guide 26. The inlet end 32 is thus provided with a wedge shape and is configured to guide the distal section edges D1, D2 and the lateral portion E0 of the blank 2 below the guide 26. This allows partial guidance of the leading edge of the blank 2 below the guide 26. The inlet end 32 of the guide 26 can be located in the inlet section I where the blank 2 is not laterally guided.

[0057] AsFigure 5b As shown, the longitudinal guiding part 36 has alignment surfaces 40 configured to abut against the inner segment edges S1, S2 of the blank 2. The alignment surfaces 40 of the guide 26 can be flat. Alternatively, as Figure 5b shown, the alignment surfaces 40 can be provided with grooves 41. The grooves 41 are configured to receive the selected inner alignment edges S1, S2 of the blank 2.

[0058] In the inlet section I, the alignment surfaces 40 of the guide 26 can be positioned at a certain lateral distance from the selected inner alignment edges S1, S2. In this way, the guide 26 does not contact the guided edge on the blank 2 until the lateral part E0 of the blank 2 is positioned below the guide 26.

[0059] As Figure 7 shown, the alignment module 11 is positioned downstream of the feeder module 10. The feeder module 10 includes a loading surface 42 configured to receive a stack of blanks 2. The loading surface 42 includes a plurality of drive belts 44 configured to contact the lowermost blank 2 in the stack and drive the lowermost blank 2 forward in the transport direction T.

[0060] The lower conveyor 24 is laterally positioned such that the lateral part E0 of the blank 2 extends further in the lateral direction and is not supported. The drive belt 44 located on the farthest side and arranged at the selected guiding edges S1, S2 of the blank 2 is positioned further outward in the lateral direction compared to the lower conveyor 24 in the alignment module 11.

[0061] This forms a lateral gap d2 in the transport path. However, the central part of the blank 2 is supported by at least one conveyor 24. Therefore, the gap d2 provides a distance over which the distal lateral segment edges D1, D2 of the blank 2 are not supported. The gap d2 allows the distal lateral segment edges D1, D2 to vertically descend under the action of gravity as the blank exits the feeder module 10. This helps the inclined inlet end 32 to guide the distal lateral segment edges D1, D2 located below the guide 26.

[0062] The upper alignment module may further include a slider 28. The slider 28 is configured to contact the blank lateral to the guide 26 and prevent its vertical movement.

Claims

1. An alignment module (11) for a converting machine (1), the alignment module being configured to correct the lateral position of a blank (2) transported through the converting machine along a transport direction (T), the blank including a first lateral outer peripheral edge (6a) and a second lateral outer peripheral edge (6b), wherein the first lateral outer peripheral edge and the second lateral outer peripheral edge are arranged on opposite sides of a central longitudinal axis (C) of the blank and extend along the transport direction. Wherein the alignment module includes at least one alignment device (30a; 30b), the alignment device having an upper pressing member (22), a lower conveyor (24) and a guide (26). And wherein the upper pressing member and the lower conveyor are configured to receive and transport the blank in a gap therebetween, and wherein the guide is an elongated rod provided with a lateral guiding surface (40) and extends along the transport direction. Characterized in that The guide also has a downwardly inclined inlet end (32) configured to guide a lateral portion (E0) of a blank located below the guide while bringing a lateral guide surface (40) into contact with inner segment edges (S1, S2) of the blank, the inner segment edges being arranged closer to the central longitudinal axis of the blank than the lateral portion of the blank located below the guide.

2. The alignment module according to claim 1, wherein the lower conveyor (24) is positioned such that the lateral portion (E0) of the blank is not supported by the lower conveyor.

3. The alignment module according to claim 1 or 2, wherein the alignment guide is provided with a groove (41), and wherein the groove is configured to hold the inner segment edges (S1, S2) of the blank.

4. The alignment module according to any one of the preceding claims, wherein the alignment module includes an inlet portion (I), in which the upper pressing member is arranged at a distance from the lower conveyor, and wherein the downwardly inclined inlet end of the guide is located in the inlet portion (I).

5. The alignment module according to claim 1, wherein the alignment guide is laterally displaceable.

6. The alignment module according to claim 1, wherein the upper alignment module further includes a slider, and wherein the connection axis (AC) of the slider coincides with the connection axis of the guide rail.

7. A converting machine (1), which includes the alignment module (11) according to any one of the preceding claims, and wherein the converting machine further includes a folding module (16) and a blank rotation module (17) configured to rotate the blank by 90°, and wherein a second alignment module (9) is arranged between the blank rotation module and the folding module.

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