Stacker module for converting machines

Abstract

The present invention relates to a transfer module (26) for a folding-gluing machine (1), the transfer module comprising a lower conveyor (36) adapted to receive folded boxes (2) therebetween and to convey the folded boxes in a conveying direction (D) towards a loading surface (90) positioned downstream in the stacker module, and an upper conveyor (38). The upper conveyor (38) of the transfer module extends further in the conveying direction than the lower conveyor (38), the lower conveyor comprising first and second conveyor belts (38a, 38b), each having an entrance end (67a, 67b) and an exit end (65a, 65b), the exit ends being displaceable in the conveying direction.

Description

[Technical field]

[0001] The present invention relates to a converting machine for producing folded boxes from sheet blanks, in particular to a coordinating section for stacking and bundling the folded boxes together. [Background technology]

[0002] Converting machines are used in the packaging industry to transform sheet-like blanks, such as corrugated and paperboard blanks, into folded boxes, also called flat-folded boxes. These machines are often referred to as folding-gluing machines and are configured to convert the blanks into folded boxes by successively folding and gluing the blanks. The resulting folded boxes have a flat shape and multiple boxes can be stacked and adjusted together in a bundle for ease of transport and storage.

[0003] However, when forming a coordinated stack of folded boxes in a folding and gluing machine, there are many moving machine parts that contact the edges of the boxes, which can produce an uneven stack and cause damage to the boxes, compromising their functional and aesthetic properties.

[0004] US Patent No. 3,224,761 discloses a module for stacking sheets in a coordinated manner, the module comprising an upper conveyor extending over a stack holder and a nozzle providing compressed air so that the sheets adhere to the upper conveyor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Pat. No. 3,224,761 [Patent Document 2] European Patent No. 3481756 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above mentioned problems, it is an object of the present invention to prevent damage to folding boxes when adjusting a stack of stacked folding boxes. [Means for solving the problem]

[0007] This problem is solved by a transfer module according to claim 1. Further advantageous features of the invention are defined in the dependent claims.

[0008] According to a first aspect of the present invention, there is provided a transfer module for a folding and gluing machine, the transfer module comprising a lower conveyor and an upper conveyor adapted to receive a folded box therebetween and to transport the folded box in a conveying direction towards a loading surface positioned downstream in a stacker module, the upper conveyor of the transfer module extending further in the conveying direction than the lower conveyor, the lower conveyor comprising first and second conveyor belts each having an entrance end and an exit end, the exit end being displaceable in the conveying direction.

[0009] The upper conveyor is configured to extend across the loading surface within the stacker module, and the displaceable exit end of the lower conveyor is configured to vary the distance between the exit end of the lower conveyor and the loading surface within the stacker module.

[0010] The present invention is based on the recognition that a confined and limited space for the folded boxes can be created by the position of the upper and lower conveyors, which prevents the folded boxes from undesired movement and misalignment and guides the folded boxes downwards to form an aligned stack on the loading surface in the stacker module.

[0011] The outlet end of the lower conveyor belt may be individually displaceable at different longitudinal positions in the conveying direction.

[0012] In an advantageous embodiment, the upper conveyor comprises a first conveyor belt and a second conveyor belt, each having a distal inlet end and a distal outlet end, and the distal outlet end of the first conveyor belt and the distal outlet end of the second conveyor belt are individually displaceable in the conveying direction so that the protrusion in the conveying direction can be varied, whereby the protrusion of the first conveyor belt and the second conveyor belt of the upper conveyor across the loading surface in the stacker module can be varied.

[0013] In one embodiment, the upper conveyor of the transfer module extends further in the conveying direction than the lower conveyor, the upper conveyor extending across the loading surface in the stacker module.

[0014] In one embodiment, the upper conveyor extends and is configured to extend across the loading surface by at least 50% of the length of the loading surface within the stacker module.

[0015] In one embodiment, the distal exit end of the first upper conveyor belt and the distal exit of the second upper conveyor belt can be positioned at different longitudinal positions relative to each other. The first conveyor belt and the second conveyor belt can be arranged parallel to each other.

[0016] In one embodiment, each of the first and second upper conveyor belts is mounted on an upper frame portion having a fixed frame portion and a movable frame portion, the movable frame portion including first and second distal exit rollers defining distal exit ends of the first and second upper conveyor belts.

[0017] In one embodiment, each of the first and second lower conveyor belts is mounted on a lower frame portion having a fixed frame portion and a movable frame portion, the movable frame portion including a distal roller that defines a distal exit end of the first and second lower conveyor belts.

[0018] In one embodiment, the first and second roller assemblies are connected to the movable frame portion and configured to follow the movement thereof.

[0019] In one embodiment, the first and second lower conveyor belts and the first and second upper conveyor belts are laterally movable such that the lateral distance between the conveyor belts can be modified.

[0020] In one embodiment, the first and second lower conveyor and the first and second upper conveyor belts are guided by displaceable compensation rollers located on the fixed frame part, which are configured to change the travel path of the conveyor belts to modify their contact length with the folding cartons.

[0021] In one embodiment, support surfaces in the transfer module are positioned between the upper and lower conveyors, and these support surfaces are inclined upwards in the conveying direction at an angle ranging from 1° to 15°, preferably between 3° and 7°, and most preferably about 5°. This allows the folded boxes to move by gravity caused by the inclination so that their rear trailing edges can abut against the ejector surface and form an aligned pile.

[0022] According to a second aspect of the present invention there is provided a transport and stacking assembly for a folding and gluing machine, the assembly comprising a transport module and a stacker module, the stacker module comprising a loading surface and an ejector, the loading surface being inclined upwards in a conveying direction.

[0023] The support surface in the transfer module and the loading surface in the stacker module may have substantially the same slope.In one embodiment, at least a portion of the ejector is positioned upstream of distal exit rollers of the first and second lower conveyor belts.

[0024] According to another aspect of the present disclosure, it relates to a stacker module for a folding-gluing machine, the stacker module being positioned downstream of the transfer module in a conveying direction of the folding-gluing machine and configured to receive folded boxes from a conveyor in the transfer module, the stacker module comprising: a loading surface configured to receive a plurality of folded boxes to form a stack and to vertically descend as the number of folded boxes on the loading surface increases; and a linearly movable ejector configured to be moved from a retracted position to an extended position to eject the stack of folded boxes from the loading surface; the stacker module further comprising a front abutment guide configured to move between an abutment position where the front abutment guide is positioned in front of the front leading edges of the folded boxes as they are deposited on the loading surface, and a clearing position where the front abutment guide is positioned away from the stack so that the ejector can clear the stack from the loading surface.

[0025] This is based on the recognition that a confined and limited space for the folding boxes can be created by the front abutment guide, which prevents the folding boxes from undesired movement and misalignment, and guides the folding boxes downward to form an aligned stack on the loading surface in the stacker module.

[0026] In one embodiment, the stacker module further comprises a control unit configured to synchronize movement of the ejector such that the ejector is in a retracted position when the front abutment guide is in an abutment position, and is in an extended position when the front abutment guide is in a clear position.

[0027] The loading surface can be configured to descend in a stepwise manner each time a batch of boxes is fed. Alternatively, the loading surface can be configured to descend continuously as folded boxes are presented to the loading surface in a continuous feed. In one embodiment, the loading surface can be modified for a stepwise or continuous descending.

[0028] In one embodiment, the front abutment guide comprises a first abutment plate and a second abutment plate arranged side by side. The first and second abutment plates may be laterally displaceable relative to one another. In one embodiment, the first and second abutment plates are longitudinally displaceable relative to one another and in the conveying direction.

[0029] In one embodiment, the ejector comprises a first pusher and a second pusher arranged laterally relative to one another, each pusher being linearly displaceable in the conveying direction and configured to move in unison between a retracted position and an extended position.

[0030] The first and second pushers may be laterally and longitudinally displaceable relative to one another such that their retracted and extended positions are different.

[0031] In an embodiment, the stacker module further comprises an upper guide configured to move between a clear position vertically away from the top surface of the stack and a guide position in which the upper guide is positioned closer to the top surface of the stack, the upper guide being in the guide position when the ejector is moved from the retracted position.

[0032] The upper guide can be synchronized to be in a guiding position during a sweep descent of the completed stack onto the loading surface and is configured to follow the downward movement of the loading surface.

[0033] The upper guide can be positioned adjacent to the top of the stack, i.e. before the ejector clears the stack from the loading surface. A faster downward movement of the stack is possible because the sheets remain stacked on top of each other during the downward movement. This in turn allows for a higher overall production speed and prevents the pile from being disturbed. This is considered advantageous for boxes with low density and high air resistance, which would otherwise be at risk of "flying" as the loading surface descends.

[0034] In an embodiment, the upper guide comprises first and second elongate guide members extending in the conveying direction. In an embodiment, the lateral distance between the first and second guide members may be modified.

[0035] The ejector may be positioned laterally of the first and second lower conveyor belts, and is preferably positioned laterally of the first and second guide members.

[0036] In an embodiment, the guiding position of the upper guide can be modified to accommodate the desired height of the stack. The upper guide can be movable at the same speed as the loading surface. Optionally, the upper guide can be deactivated and fixedly positioned in the clear position.

[0037] The upper guide aligns the stack of folded boxes so that it can be set to lower to compress the stack before it is transferred into the strapping module. This provides a consistent height of the stack so that the bundle of boxes exiting the strapping module has the same height. The term "aligned" means that the boxes are aligned.

[0038] In an embodiment, the front stop guide remains stationary when the loading surface is lowering. Instead, the front stop is moved vertically upwards when the loading surface is lowering. When the stack of sheets moves downwards, only the top sheets in the stack need to be restricted in their forward movement of the sheets. Thus, the front stop can be positioned only where it is needed. This reduces the vertical extension length of the front stop and the movement required to move the front stop in a clear position so that the stack can be cleared.

[0039] The ejector can be connected to the actuator and configured to move at a first speed when the stack is present in the stacking module and at a second speed when the stack is present in the strapping station, the first speed being greater than the second speed.

[0040] The distance determined for the first speed can be modified depending on the longitudinal length of the folding box in the conveying direction.

[0041] According to a second form of the present disclosure, it relates to a transport and stacking assembly for a folding-gluing machine, the assembly comprising a stacker module and a transport module as claimed in any one of the preceding claims, the transport module comprising a lower conveyor and an upper conveyor adapted to receive folded boxes therebetween and transport the folded boxes in a conveying direction towards a loading surface positioned downstream in the stacker module, the upper conveyor and the lower conveyor comprising a first conveyor belt and a second conveyor belt each provided with a distal inlet end and a distal outlet end, the distal outlet end of the first conveyor belt and the distal end of the second conveyor belt being individually displaceable in the conveying direction such that their extension across the loading surface in the stacker can be varied.

[0042] According to a third aspect of the disclosure of the present invention, it relates to a method for adjusting a stack of folded boxes in a transfer and stacking assembly as claimed in the preceding claims, the method comprising the steps of aligning, in the transfer module, a lower conveyor with a rear trailing edge of the folded boxes, aligning, in the transfer module, an upper conveyor with a front leading edge of the folded boxes, moving, in the stacker module, a front abutment guide into a guiding position in which the upper guide is positioned at a first distance from the top surface of the stack, transporting the folded boxes between the upper and lower conveyors towards a loading surface in the stacker module, lowering the loading surface in the stacker module, lowering the loading surface such that when the stack is completed and the loading surface is at a final loading height, a sweep lowering is performed, whereby the loading surface is lowered to the sweep position, moving the front abutment guide into a clearing position vertically farther away from the top surface of the stack and further away from the top surface of the stack than the guiding position, and moving the stack from the loading surface.

[0043] In an embodiment, the method may further comprise lowering the upper guide so as to be positioned against the top surface of the stack during the sweep descent, during which the loading surface is moved from the final loading height to the sweep position.

[0044] Further advantages and features will become apparent from the following description of illustrative embodiments of the invention and from the accompanying drawings in which like reference numerals refer to like features and in which: [Brief description of the drawings]

[0045] [Figure 1a] FIG. 1 is a schematic diagram of a folding and gluing machine according to an embodiment of the present invention. [Figure 1b] FIG. 1b is a schematic diagram of the conditioning section of the folding and gluing machine of FIG. 1a. [Figure 2a] 1A shows an exemplary type of blank and a folded box produced by the folding and gluing machine of FIG. 1A. [Figure 2b] 1A shows an exemplary type of blank and a folded box produced by the folding and gluing machine of FIG. 1A. [Figure 2c] 1A shows an exemplary type of blank and a folded box produced by the folding and gluing machine of FIG. 1A. [Figure 2d] 1A shows an exemplary type of blank and a folded box produced by the folding and gluing machine of FIG. 1A. [Diagram 3] 1 is a schematic diagram of a conditioning section comprising a transfer module, a stacker module and a bundling module according to an embodiment of the present invention; [Figure 4] FIG. 2 is a schematic view of a conditioning section according to the invention when receiving a stream of folded boxes; [Diagram 5] 2 is a schematic diagram of a transfer module according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic perspective view of a transfer module according to the present invention; [Figure 7] FIG. 6 is a schematic cross-sectional view of the transfer module of FIG. 5. [Figure 8]FIG. 2 is a schematic cross-sectional view of a stacker module according to the present invention; [Figure 9] FIG. 13 is a detailed schematic perspective view of an upper guide in a stacker module according to an embodiment of the present invention. [Figure 10] FIG. 13 is a detailed schematic perspective view of a front abutment guide in a stacker module according to an embodiment of the present invention. [Figure 11a] 2 is a schematic perspective view of a loading surface of a stacker module according to an embodiment of the present invention; FIG. [Figure 11b] 2 is a schematic perspective view of a loading surface of a stacker module according to an embodiment of the present invention; FIG. [Figure 11c] 2 is a schematic perspective view of a loading surface of a stacker module according to an embodiment of the present invention; FIG. [Figure 12a] 1A-1C are schematic diagrams illustrating example positioning of an ejector according to an embodiment of the invention having displaceable first and second pushers. [Figure 12b] 1A-1C are schematic diagrams illustrating example positioning of an ejector according to an embodiment of the invention having displaceable first and second pushers. [Figure 13] FIG. 4 is a schematic diagram illustrating adjustment of ejector speed and acceleration according to an embodiment of the present invention. [Figure 14] FIG. 2 is a schematic perspective view of a single inverter. [Figure 15] FIG. 2 is a schematic perspective view of a stacker module according to an embodiment of the present invention as viewed in the conveying direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] Reference is made to the figures, and in particular to Figure 1a, which shows a converting machine in the form of a folding-gluing machine 1. The folding-gluing machine folds and glues a blank 2' as shown in Figures 2b and 2c to form a folding box 2 as a folding box as shown in Figures 2a and 2d. The blank 2' is provided with a peripheral edge 4 defining the shape of flaps 6 and with fold lines 8, which allow folding of the intermediate blank 2' along a predetermined line.

[0047] Such blanks 2' are typically produced on another converting machine, such as a flat bed die cutter or a rotary die cutting machine, which accepts and converts a flat, typically rectangular, sheet substrate of corrugated or paperboard into a blank 2'.

[0048] Referring back to Fig. 1a, the folding-gluing machine 1 of the present invention comprises a series of different workstations, including from the inlet to the outlet, a feeder module 10, a folding pre-breaking module 12, a gluing module 14, a folding module 16, a transfer module 18 and an outgoing station or collection table 19. After the folding and gluing modules of the converting machine, a conditioning section 20 can be provided for counting and separating the bundles of folded boxes 2 and arranging them together in a bundled stack. As shown in Fig. 1b, such conditioning section 20 of the folding-gluing machine 1 comprises a counter and separator unit 22, optionally a single inverter 24, a transfer module 26 arranged after the single inverter 24, a stacker module 28 configured to arrange the folded boxes in a stack and a bundling module 30.

[0049] The folding and gluing machine 1 further comprises a control system which may comprise a main centralized control system and a separate peripheral control system. For example, the coordinating section 20 may comprise a separate peripheral control unit 43. The combination of centralized and peripheral control systems allows certain modules to retrieve and process some data locally, while the central control unit 13 of the centralized control system may be dedicated to controlling the overall operation of the folding and gluing machine 1.

[0050] The counter and separator unit 22 is configured to count and condition the stream of folded boxes into separated batches having a predetermined quantity, after which the separated batches can be provided with a perimeter band and bundled together in a bundling module 30 located downstream.

[0051] A single inverter 24 may be provided downstream of the counter and separator unit 22. The single inverter 24 is configured to rotate 180° for every second batch of boxes while allowing the next batch to pass in a straight line. Such a single inverter is described in EP 3481756 and is shown diagrammatically in Figure 14.

[0052] Rotating the batch of boxes by 180° allows the stack height to be equalized and better adjusted so that the stack is substantially vertical. This is advantageous for some types of folding boxes 2 that have an uneven thickness due to the shape of the folds. The uneven thickness often occurs when the folds result in several sheet thicknesses overlapping each other. As shown in FIG. 14, the single inverter 24 comprises an upper belt conveyor 25a and a lower belt conveyor 25b and is rotatable about an axis A so that the single inverter can receive and rotate 180° a batch of folding boxes 2 between the upper and lower conveyors 25a, 25b as it rotates.

[0053] 4, the folded boxes 2 from the single inverter 24 or directly from the counter-separator module 22 are further transported downstream to a transfer module 26, a stacker module 28 and a bundling module 30. The transfer module 26 transports batches of folded boxes 2 and positions the batches in a downstream positioned stacker 28 where they form a stack. The stacker module 28 collects the boxes 2 such that the boxes 2 are aligned to form a stack of overlapping boxes, after which the stack is introduced into the bundling module 30.

[0054] Details of the transfer module 26 according to an embodiment of the invention will now be further described with reference to Figures 3 to 7. As can be seen in the figures, the transfer module 26 comprises an outer housing and a structural frame 34 on which an upper conveyor 36 and a lower conveyor 38 are mounted. The folded boxes 2 are received from an upstream positioned module such as the single inverter 24 or directly from the counter-separator module 22. The upper and lower conveyors 36, 38 are configured to transport a stream of folded boxes 2 between them and to position the folded boxes 2 in the downstream positioned stacker module 26. A support surface S is thus defined between the upper and lower conveyors 36, 38.

[0055] The transfer module 26 may further include a control interface 40 and a display 42. A peripheral control unit 43 may be located near and operatively connected to the control interface 40 to enable an operator to monitor and change settings associated with the transfer module 26. Alternatively, the peripheral control unit 43 may be located in the counter-separator module 22 and operatively connected to the transfer module 26.

[0056] The upper and lower conveyors 36, 38 are provided with a longitudinal extension E which coincides with the longitudinal direction D of the folding-gluing machine 1. The longitudinal direction D in the folding-gluing machine 1 can be defined as the conveying direction D of the blanks 2' or folding boxes 2 through the folding-gluing machine 1.

[0057] In the illustrated embodiment, the upper conveyor 36 comprises a first upper conveyor belt 36a and a second upper conveyor belt 36b arranged in a pair. Similarly, the lower conveyor 38 comprises a first lower conveyor belt 38a and a second lower conveyor belt 38b arranged in a pair. The conveyor belts 36, 38 are in the form of endless belts and are guided by rollers 37 mounted on the upper and lower frame components 46, 45 so that the position of the conveyor belts is maintained. The upper conveyor belts 36a, 36b are connected to a drive mechanism 48 comprising drive rollers 50 and a motor (not shown) for driving the belts into motion. Similarly, the lower conveyor belts 38a, 38b are further connected to a drive mechanism 41 comprising drive rollers 82. To accomplish this, the conveyor belts 36 a , 36 b , 38 a , 38 b may be provided with a contact side and a traction side, the traction side being recessed for engagement with a corresponding recessed drive roller 50 .

[0058] Each of the pair of upper conveyor belts 36a, 36b has an extension within the transfer module 26 between an entrance end 56 and an exit end 58. The entrance end 56 is defined by entrance rollers 60a, 60b and the exit end is defined by exit rollers 62a, 62b. These ends 56, 58 define the overall longitudinal contact length of the upper conveyor belts 36a, 36b that contacts the folding cartons 2.

[0059] Thus, the first and second upper conveyor belts 36a, 36b may have first and second inlet ends 60a, 60b and first and second outlet ends 62a, 62b. Similarly, the first and second lower conveyor belts 38a, 38b may have first and second inlet ends 67a, 67b and first and second outlet ends 65a, 65b. The inlet ends 60a, 60b, 67a, 67b and the outlet ends 62a, 62b, 65a, 65b may be defined by rollers.

[0060] The first and second upper conveyor belts 36a, 36b may include a pair of movable entrance rollers 60a, 60b configured to move between a receiving position R and a transport position T. The entrance rollers 60a, 60b may be mounted on an elongated frame 63 that is received in cooperating slide rails 64 on the upper frame 46 of the transfer module 26. The vertical movement of the first and second entrance rollers 60a, 60b of the upper conveyor belts 36a, 36b may be determined by a sensor 61 positioned upstream.

[0061] As shown in Fig. 7, in the receiving position R, the movable first and second inlet rollers 60a, 60b of the upper conveyor belts 36a, 36b are positioned far from the lower conveyor belts 38a, 38b at a first distance d1 from the lower conveyor belts 38a, 38b. This creates a funnel-shaped inlet between the upper and lower conveyor belts 36a, 36b, 38a, 38b such that the batch of folding boxes is guided between the upper and lower conveyor belts 36a, 36b, 38a, 38b. In the transport position T (as shown by the dashed rollers), the movable distal inlet rollers 60a, 60b of the upper conveyor belts 36a, 36b are positioned at a second distance d2 from the lower conveyor belts 38a, 38b. In the second position, the movable distal entrance rollers 60a, 60b are positioned closer to the lower conveyor belts 38a, 38b such that the folding box 2 is sandwiched between the upper and lower conveyors 36, 38. Thus, the second distance d2 is less than the first distance d1.

[0062] The vertical movement of the first and second distal inlet rollers 60a, 60b of the upper conveyor belts 36a, 36b is coordinated with the register control of the fold-glue 1 and the position of the batch. The control unit 43 of the coordination section 20 or the control unit of the counter-separator module 22 can be configured to determine the arrival time of the batch of folded boxes at the inlet 56 of the transfer module 26 and to activate the actuator 57 so as to displace the distal inlet rollers 60a, 60b accordingly.

[0063] At the exit end 58 of the transfer module 26, the distal ends 62a, 62b of the first and second upper conveyor belts 36a, 36b extend further in the longitudinal direction D than the distal exit ends 66a, 66b of the first and second lower conveyors 38a, 38b. Preferably, the projection length between the distal exit ends 66a, 66b of the upper conveyors 62a, 62b and the distal exit ends 66a, 66b of the lower conveyor belts 38a, 38b, i.e. the distance d3, can be varied. Advantageously, this distance d3 corresponds to the longitudinal length Lb1, Lb2 (see Figs. 2a to 2d) of the folding boxes 2 generated in the longitudinal direction D. It can be adjusted for different longitudinal lengths Lb1, Lb2 of the folding boxes 2. The distal exit ends 62a, 62b, 66a, 66b are movable whilst the distal entrance rollers 60a, 60b, 67a, 67b can remain in a fixed longitudinal position during transport of a batch of folding cartons 2.

[0064] The distal exit ends 62a, 62b of the upper conveyor belts 36a, 36b are preferably provided with a projection length d3 so as to be in close proximity to a front abutment guide 70 of the stacker module 28. The front abutment guide 70 comprises at least one abutment surface 72a, 72b, preferably two abutment surfaces 72a, 72b. The first front abutment surface 72a and the second front abutment surface 72b may be in the form of a first abutment plate 72a and a second abutment plate 72b. The term "close proximity" may be defined as a projection distance d3 corresponding to more than 50% of the longitudinal length of the folding box 2, such as 75 or 90%. A short distance between the abutment surfaces 72a, 72b and the upper conveyor belts 36a, 36b is preferred, since this prevents the upper conveyor belts 36a, 36b from touching the abutment surfaces 72a, 72b and at the same time ensures maximum guiding of the folding box 2. This makes it possible to create a closed space under the upper conveyor belts 36a, 36b in which the folding box 2 is trapped.

[0065] As shown in Figures 2a to 2d, 12a and 12b, some folding boxes 2 do not have a straight front edge 3 or a straight rear edge 5. This applies to some types of boxes, such as straight boxes or crash lock bottom boxes. The lengths of the longitudinal protrusions d3 of the first upper conveyor belt 36a and the second upper conveyor belt 36b may be different from each other. Thus, the front abutment guide 70 can be provided with corresponding first abutment surfaces 72a and second abutment surfaces 72b that are also movable in the longitudinal direction D to ensure that the first abutment surfaces 72a and second abutment surfaces 72b are adjacent to the distal exit ends 62a, 62b of the first and second upper conveyor belts 36a, 36b.

[0066] As best seen in Figures 3 and 7, the first and second upper conveyor belts 36a, 36b are received in an upper frame assembly 46 comprising a fixed frame component 46a and a movable frame component 46b. The movable frame component 46b and the fixed frame component 46a are movably connected to each other. Advantageously, a slide rail connection can be provided between the fixed frame 46a component and the movable frame 46b component such that the movable frame component 46b, on which the conveyor belts 36a, 36b are mounted, can be slidably moved in the conveying direction D. This allows for the modification of the overhang length d3 of the upper conveyor belts 36a, 36b. This further allows for the distal outlet ends 62a, 62b of the first and second upper conveyor belts 36a, 36b to be movably arranged in the conveying direction D.

[0067] As best seen in Figure 3, the movable frame component 46a may be connected to an actuator 47 which is displaceable by a motor 49. The actuator 47 may be a mechanical actuator 47, but it is also possible to use a pneumatic / hydraulic actuator 47. The actuator 47 is preferably motorized and configured for automatic displacement based on information from the main control unit 13 or the peripheral control unit 43. For example, the overhang length d3 of the upper conveyor belts 36a, 36b may be determined from the folding box dimensions entered into the user interface 40.

[0068] When the first and / or second distal exit ends 62a, 62b of the upper conveyor 36 and the first and / or second distal exit rollers 66a, 66b of the lower conveyor 38 change their longitudinal positions, the total longitudinal contact length of the respective conveyor belts 36a, 36b, 38a, 38b changes. To accommodate different longitudinal lengths of the same conveyor belt, the travel path P of the conveyor belts 36, 38 is changed. This can be achieved using adjustable compensation rollers 39a, 39b arranged on the fixed frame components 45a, 46a. The adjustable compensation rollers 39a, 39b can be linearly movable to change the travel path P of the conveyor belts 36, 38. This allows the distal exit rollers 62a, 62b, 66a, 66b to be positioned at different longitudinal positions while the distal entrance rollers 60a, 60b, 67a, 67b remain fixed.

[0069] The first and second lower conveyor belts 36a, 36b may be positioned about first and second roller assemblies 80a, 80b that comprise a series of idle rollers positioned near one another. The roller assemblies 80a, 80b provide a stable support surface for the batches of folding boxes and guide the lower conveyor belts 38a, 38b. The drive rollers 82 are positioned on the lower frame structure 45 and may be provided with a transverse length such that the drive rollers 82 are configured to contact both the first and second lower conveyor belts 38a, 38b and drive them in unison.

[0070] The distal outlet ends 66a, 66b of the first and second lower conveyor belts 38a, 38b may also be individually movable in the longitudinal direction D, which allows the lower conveyor belts 38a, 38b to be positioned in different longitudinal positions and also relative to each other. The first and second lower conveyor belts 38a, 38b are thus provided with a variable projection length in the longitudinal direction D. This allows adjustment according to the shape of the rear trailing edge 5 of the folding box 2.

[0071] As mentioned above and similar to the upper conveyor belts 36a, 36b, the length of the first and second lower conveyor belts 38a, 38b can also be modified by providing first and second longitudinally movable distal exit rollers 65a, 65b. To accomplish this, the lower conveyor belts 38a, 38b are connected to a movable frame component 45b that is located in the lower frame 45 and slidably connected to a fixed frame component 45a.

[0072] As shown in the detailed view of FIG. 7, first and second roller assemblies 80a, 80b may be provided having variable contact lengths with the first and second lower conveyor belts 38a, 38b. The roller assemblies include a series of rollers 82 mounted in a chain. The roller assemblies 80a, 80b are disposed within a loop of the endless conveyor belts 38a, 38b. In that way, there is no interference between the roller assemblies and the conveyor belts 38a, 38b. The roller assemblies 80a, 80b include a number of pin-like links 84 connected to each other at a number of pivot axles 86. The rollers 82 are rotatably connected to a roller frame component 88 connected to the pivot axles 86.

[0073] The roller assemblies 80a, 80b are connected to the movable frame component 45b such that as the movable frame component 45b is extended or retracted in the longitudinal direction D, the roller assemblies 80a, 80b follow its movement.

[0074] The transfer module 26 deposits the folding boxes 2 into a stacker module 28. As best seen in Figure 4, the stacker module 28 comprises a loading surface 90, a front abutment guide 70 with a first front abutment surface 72a and a second front abutment surface 72b, and an ejector 76.

[0075] It is desirable to deposit the folded boxes 2 on the loading surface 90 in the stacker module 28 so as to preform a calibrated stack of superimposed boxes 2. The term "calibrated" means that the boxes are aligned by their edges and the stack is provided with a consistent vertical height so that the stack is straight. The conveyors 36, 38 and the front abutment surfaces 72a, 72b of the transfer module 26 are configured to confine the folded boxes 2 within a limited space. Since the folded boxes 2 follow the conveying direction D while being endowed with substantial kinetic energy, it is preferable to initially align the folded boxes by the front leading edge 3 of the boxes by using the first and second front abutment surfaces 72a, 72b as abutments. The abutment surfaces 72a, 72b act as stop surfaces, which prevent further forward movement of the front leading edge 3.

[0076] The ejector 76 is arranged in the stacker module 28 to clear the stack from the loading surface 90 and further transport the stack to the strapping unit 30. The ejector 76 is positioned behind the stack in the conveying direction D and is able to further align the rear trailing edge 5 of the folding carton 2. To achieve this, the ejector 76 is provided with a vertical contact surface 78 having a vertical length greater than the maximum height of the stack.

[0077] 4, the distal exit ends 66a, 66b of the first and second lower conveyor belts 38a, 38b may be vertically aligned with the vertical contact surface 78 of the ejector 76. This allows for limiting the distance between the ejector 76 and the rear trailing edge 5 of the folded boxes 2. This in turn shortens the distance the ejector 76 needs to push the formed stack 2 of folded boxes into the bundling unit 30. This mitigates a potential problem that the longer the ejector 76 needs to displace the stack the more damage that can be caused by the trailing edge 5 of the folded boxes 2 in the stack.

[0078] The first and second lower conveyor belts 38a, 38b in the transfer module 26 and the loading surface 90 in the stacker module 28 can be provided with an upwardly inclined surface S in the conveying direction D. The transfer module 26 is thus configured to guide the front leading edges 3 of the folding boxes 2 upwards.

[0079] The transfer module 26 deposits the folded boxes 2 into the stacker module 28 so that the front leading edge 3 of the box contacts the first and second front abutment surfaces 72a, 72b of the front abutment guide 70. The loading surface 90 can be provided with an upward inclination angle of 2° to 7°, preferably 5°, which provides for an additional rearward movement of the box 2 so that the box 2 is aligned by the rear trailing edge 5 of the box 2 against the vertical contact surface 78 of the ejector 76. This helps to adjust the stack to ensure that the ejector 76 contacts the rear trailing edge 5 of the folded box 2. The inclination angle at the transfer module 26 facilitates the positioning of the folded box 2 at the corresponding inclination angle of the loading surface 90 in the stacker module.

[0080] The loading surface 90 is configured to receive a batch or series of batches of inverted and non-inverted boxes 2 and descend until a predetermined number of boxes have been loaded onto the loading surface 90. This predetermined number will typically depend on the number of boxes 2 that need to be contained in each bundle from the strapping module 30.

[0081] As best seen in FIG. 11b, the loading surface 90 is movable between an initial loading height h1 and a sweep height h3. The initial loading height h1 and the sweep height h3 may be fixed distances that can be modified and defined by a control system. However, when the desired number of boxes per bundle changes, a vertical sweep distance may be provided between the final loading height h2 and the sweep height h3. A sweep drop distance is thus defined between the heights h2 and h3. During this sweep drop distance, no boxes are deposited on the loading surface 90. The sweep drop distance may be changed for different heights of stacks to be produced. This results in the final loading height h2 being dependent on the number of folded boxes 2 in the stack.

[0082] 11a-11C, the loading surface 90 is connected to a drive actuator 92 configured to apply a downward velocity to the loading surface 90. This velocity can be set in relation to the velocity of the upper and lower conveyors 36, 38 within the transfer module 26. The velocity of the loading surface 90 during ascent and / or descent can also be set at a maximum and independent of the velocity of the conveyors 36, 38.

[0083] In one embodiment, the loading surface 90 descends continuously. In another embodiment, the loading surface 90 can descend in discontinuous steps. The stepwise and discontinuous descent can be set to provide a series of pre-determined distances for each batch received on the loading surface 90. This is advantageous as the loading surface 90 remains stationary as the folding boxes 2 are stacked, thus preventing potential friction and misalignment.

[0084] The loading surface 90 can be comprised of two elongated, spaced apart support rails 90a, 90b. The rails 90a, 90b provide a minimal contact surface against the stack to reduce friction. In addition, the loading surface 90 is lightweight and can be easily moved up and down vertically.

[0085] The loading surface 90 allows for sliding movement of the stack towards the strapping module 30 as the ejector 76 pushes against the trailing edge of the stack. In one embodiment, a low friction surface such as Teflon can be used. Alternatively and in an advantageous embodiment, the loading surface 90 can include rollers 94. The rollers 94 can be idle since the moving force for transport can be provided by the ejector 76. Alternatively, at least a portion of the rollers 94 can be motorized.

[0086] The loading surface 90 can be inserted between the rear sliding surface 96 and the front sliding surface 98 in the form of a rail provided with rollers, whereby these sliding surfaces extend in the conveying direction D. The rear sliding surface 96 and the front sliding surface 98 can be arranged stationary. The rear sliding surface 96 represents an extension of the loading surface 90 which can support the rear parts of the folding boxes 2. The front sliding surface can advantageously be configured as a transition between the loading surface 90 and a stacking surface 101 situated downstream in the strapping module 30.

[0087] The front and rear slide surfaces 96, 98 may be provided with a fixed height, and preferably the slide surfaces 96, 98 are aligned with a deposition surface at the strapping zone 100 of the strapping module 30. The front slide surface 98 also allows a longer travel distance for the ejector 76 to push the stack out of the stacker module 28, thereby ejecting the stack from the loading surface 90, where it can then be conveyed over the front slide surface 98 and deposited in the strapping zone 100. The loading surface 90 and the front slide surface 98 thus enable the ejector 76 to position the stack directly into the location in the strapping zone 100 where the band will be applied around the stack.

[0088] As best seen in Figure 11a, the ejector 76 is linearly and reciprocally movable between a retracted position RP and an extended position DP. As shown in Figure 4, the ejector 76 can be positioned such that at least a portion of the ejector 76 is positioned upstream of the distal exit ends 66a, 66b of the first and second lower conveyor belts 38a, 38b.

[0089] As best seen in Figures 8, 11c, 12a and 12b, the ejector 76 can comprise a first pusher 76a and a second pusher 76b, which can be set at different longitudinal positions. Thus, the first pusher 76a can be positioned at a different longitudinal position than the second pusher 76b. This is advantageous for boxes 2 with uneven rear trailing edges, such that the first and second pushers 76a, 76b can be positioned corresponding to the shape of the rear trailing edge 5. In addition to this, this gives the possibility to align the pushers 76a, 76b with the stiffest part of the folding box 2. The first and second pushers 76a, 76b can also be laterally adjustable. This allows the first and second pushers 76a, 76b to be perfectly adapted to the size, length and overall shape of the rear trailing edge 5 of the folding box.

[0090] The pushers 76a, 76b are provided with a linear vertical contact surface 78 that corresponds to or is greater than the maximum height of the stack. The vertical contact surface 78 is advantageously positioned such that the vertical contact surface 78 aligns with the distal outlet ends 66a, 66b of the lower conveyor belts 38a, 38b. When the lower conveyor belts 38a, 38b of the transfer module 26 are displaced in the longitudinal direction D (to adjust for different sizes of folding boxes), the longitudinal positions of the first and second pushers 76a, 76b can be set accordingly. The vertical contact surface 78 limits the rearward movement of the stack.

[0091] As shown diagrammatically in Fig. 13, the movement of the ejector 76 can be adjusted so that the trajectory of the ejector 76 comprises a number of distances with different speeds and accelerations. This trajectory corresponds to the transport distance of the formed stack from the loading surface 90 to the bundling zone 100 in the bundling module 30. The ejector 76 can thus have a trajectory from an initial position behind the distal ends 66a, 66b of the lower conveyor belts 38a, 38b and move all the way to the bundling zone 100 at the extended position DP of the ejector 76. The bundling module 30 can be provided with a central cutout configured to receive the ejector 76 when present in the bundling module 30. During the bundling process, when the stack is present in the bundling module, the speed and acceleration of the ejector will be reduced to ensure bundling accuracy and to avoid marks on the folding boxes 2.

[0092] The speed and acceleration affect potential damage on the folding carton 2 during the transition between the stacker module 28 and the strapping module 30. At the same time, it is advantageous to provide a high optimized speed of the ejector 76 so that the overall production rate of the conditioning section 20 can be maintained. It has been found advantageous to provide a speed and acceleration that varies over a number of different segment distances.

[0093] The acceleration and deceleration within these predetermined distance segments can be modified. As shown, the segment distances are: T1-acceleration distance T2 - Access zone to the bundling module T3-Deceleration distance T4-Insertion Speed ​​Bundling Module T5 - Deceleration in bundling module.

[0094] The first distance T1, over which the first acceleration is applied, may depend on the longitudinal length of the folding box 2. Folding boxes 2 with shorter longitudinal lengths Lb1, Lb2 have to travel further before reaching the bundling zone 100 in the stacker. In segment T2, the acceleration is null, with an optimal speed being reached. When the ejector 76 approaches the bundling zone 100, the speed is reduced by deceleration. The insertion speed in the bundling zone 100 is constant in segment T4 to ensure a controlled positioning of the band around the stack. A further deceleration can be applied in distance segment T5, so that the bundling stack can be carefully deposited at the exit of the folding-gluing machine 1 when the stack is released from the bundling zone 100.

[0095] These distance segments T1 to T5 can be automatically defined by a program stored in the memory of the control circuit of the regulation section 20. The program can calculate the acceleration and speed depending on the format and the paper / cardboard properties such as mechanical resistance. Optionally, a production mode defining the speed and acceleration within the different distance segments T1 to T5 is selectable on the control interface 40 on the folding-gluing machine 1.

[0096] 4, 8 and 10, the front abutment guide 70 is disposed in the conveying direction in front of the loading surface 90. As mentioned above, the front abutment guide 70 may comprise a first front abutment surface 72a and a second front abutment surface 72b.

[0097] The first 72a and the second front abutment surface 72b may be in the form of a first plate 72a and a second plate 72b movably mounted on a transverse frame 73. The transverse frame extends transversely or perpendicularly to the longitudinal direction D of the folding-gluing machine 1.

[0098] Depending on the format of the folding box and in particular the transverse length of the front leading edge 3, the lateral distance between the first plate 72a and the second plate 72b can be adjusted. Typically, the longer the front leading edge 3 of the folding box 2, the greater the distance between the first plate 72a and the second plate 72b. The front abutment surfaces 72a, 72b can also be moved in the longitudinal direction (i.e. in the conveying direction D) of the folding-gluing machine 1. This further improves the support of the non-straight front leading edge 3, as mentioned above. Thus, the first and second plates 72a, 72b can be set in different lateral and longitudinal positions corresponding to the shape of the front leading edge 3 of the folding box 2.

[0099] As best seen in Fig. 8, the first plate 72a and the second plate 72b are connected to an actuator 74 and a motor 75, which may be further connected to a control unit 13, 43 of the folding-gluing machine 1. The control unit 43 may be a peripheral control unit for the adjustment section 20. The optimal positions of the first and second plates 72a, 72b may be automatically calculated by the control unit 13, 43 in relation to the dimensions of the folding box 2 when folded.

[0100] A sensor 77, such as a linear encoder, may be arranged on the front abutment guide actuator 74 and connected to the control unit 13, 43 and the motor 75. The sensor 77 may detect the position of the first plate 72a and the second plate 72b and transmit the detected position to the memory 39. This allows the motor 75 to retrieve position feedback in order to control its movement and the final position of the first and second abutment plates 72a, 72b. For subsequent jobs with folding boxes 2 of different dimensions, the actual positions of the first and second plates 72a, 72b may be retrieved from the memory 39 and the actuator 74 and the motor 75 may displace the first and second plates 72a, 72b to new optimal positions.

[0101] Additionally or alternatively, the first and second plates 72a, 72b may be manually positioned, either as a master setting or manually displaced as adjusted by a machine operator.

[0102] As shown diagrammatically in Figures 3 and 10, the first and second plates 72a, 72b are vertically movable between an abutment position SP and a clearance position CP. In the abutment position SP, the plates 72a, 72b are positioned at a lower position so as to abut the front leading edge 3 of the folded box 2. In the clearance position CP, the plates 72a, 72b are positioned higher than the support position SP so that the entire stack and the vertical face 78 of the ejector 76 can be displaced below the plates 72a, 72b without interference.

[0103] The up and down vertical reciprocating movement of the plates 72a, 72b is adjusted by the control unit 43 to be synchronized with the displacement of the ejector 76. As mentioned above, the lateral distance between the first and second contact plates 72a, 72b can be modified etc. for boxes of different shapes. To achieve this, a propulsion system for repeat orders can be used for predefined formats and shapes of folding boxes 2 stored in the memory 39.

[0104] 10 and 15, the stacker module 28 may further include an upper guide 110 configured to guide the stack during transfer from the stacker module 28 to the bundling module 30. The upper guide 110 prevents the folding boxes 2 from moving upwards during transfer to the bundling module 30 and may also adjust or compress the height of the stack.

[0105] The upper guide 110 is vertically movable between a clearance position CP and a guide position GP. When the stack is ready to be released from the stacker module 28 and moved into the strapping module 30, the upper guide 110 is lowered from the clearance position CP to the guide position GP so that it is positioned near the top surface of the stack. The upper guide 110 is dynamically positionable such that the upper guide 110 can be set depending on the height of the stack. The upper guide 110 also helps avoid the "pile spring effect" by keeping the stack adjusted to ensure transition into the strapping module 30.

[0106] Additionally, in an advantageous embodiment, the upper guide 110 can be further configured to abut against the top surface of the stack as it descends from the final loading height h2 to the clearing height h3 (see FIG. 11b). The final loading height h2 corresponds to the height of the loading surface 90 when the number of folding boxes 2 to be included in the bundle are deposited on the loading surface 90. The upper guide 110 can keep the stack adjusted during the descent by following the downward movement of the loading surface 90. Additionally, the upper guide 110 can be programmed to be positioned at a predetermined distance relative to the loading surface 90 so that the stack can be adjusted to be compressed to a predetermined height.

[0107] The upper guide 110 may comprise a first guide member 110a and a second guide member 110b. The guide members 110a, 110b may be in the form of elongated bars or blades. The guide members 110a, 110b have a longitudinal extension between the outlet 58 of the transfer module 26 and the deposition surface 101 in the bundling module 30. The first guide member 110a and the second guide member 110b may be laterally displaceable transversely or perpendicularly to the conveying direction D.

[0108] The lateral displacement can be achieved by a guide motor 111 or a pair of guide motors 111a, 11b and an actuator 112. The lateral displacement allows the upper guide members 110a, 110b to be offset laterally relative to the upper and lower conveyor belts 36a, 36b, 38a, 38b within the transfer module 26. This reduces potential interference between these elongated components. In addition to this, the lateral adjustment allows better adjustment to different widths of the folding boxes 2 so that the first and second guide members 110a, 110b can be adapted to the different widths of the boxes 2. The vertical displacement of the guide members 110a, 110b can be achieved by a guide lowering motor 113 and an actuator 114, which can be arranged to move the first and second guide members 110a, 110b correspondingly between the initial loading height h1 and the clearing height h3.

[0109] As best seen in Figs. 8 and 11, the stacker module 28 may further comprise first and second lateral side guides 120a, 120b. The lateral side guides 120a, 120b may have upper inclined surfaces to form a receiving funnel perpendicular to the conveying direction D such that the lateral sides of the folded boxes 2 in the folding-gluing machine 1 are aligned when positioned on the loading surface 90. Furthermore, a vertical wall may be disposed vertically below the first and second lateral side guides 120a, 120b. The wall laterally holds the stack as it is conveyed to the strapping unit 28 and is particularly useful for long folded boxes 2. In one embodiment, the wall may be transparent to allow an operator to visually monitor the stack alignment before the strapping module.

[0110] Those skilled in the art will recognize that the present invention is by no means limited to the exemplary embodiments described. While the present invention has been illustrated in detail in the drawings and foregoing description, such illustrations and descriptions are to be considered illustrative or exemplary and not restrictive, and the present invention is not limited to the disclosed embodiments.

Claims

1. A transfer module (26) for a folding-gluing machine (1), comprising: a lower conveyor (38) and an upper conveyor (36) adapted to receive a folding box (2) therebetween and to convey said folding box in a conveying direction (D) towards a loading surface (90) located downstream in the stacker module; the upper conveyor (36) of the transfer module extends further in the conveying direction than the lower conveyor (38); the lower conveyor comprises a first conveyor belt (38a) and a second conveyor belt (38b), each having an inlet end (67a, 67b) and an outlet end (65a, 65b); The outlet end is displaceable in the conveying direction, each of the first and second lower conveyor belts is mounted on a lower frame portion (45) having a fixed frame portion (45a) and a movable frame portion (45b); the movable frame portion includes distal rollers (65a, 65b) defining the distal exit ends of the first and second lower conveyor belts; First and second roller assemblies (80a, 80b) are connected to the movable frame portion of the lower frame portion (45) and are configured to follow the movement thereof; A transfer module (26).

2. the outlet end (65a) of the first conveyor belt (38a) and the outlet end (65b) of the second conveyor belt (38b) are individually displaceable at different longitudinal positions in the conveying direction; The transfer module of claim 1 .

3. the upper conveyor includes a first conveyor belt (36a) and a second conveyor belt (36b), each having a distal inlet end (60a, 60b) and a distal outlet end (62a, 62b); the distal exit end of the first conveyor belt and the distal exit end of the second conveyor belt are individually displaceable in the conveying direction so that their protrusion in the conveying direction can be varied. A transfer module according to claim 1 or 2.

4. the distal exit end of the first conveyor belt (36a) and the distal exit end of the second conveyor belt (36b) may be positioned at different longitudinal positions relative to each other; The transfer module of claim 3 .

5. the first conveyor belt and the second conveyor belt of the upper conveyor are arranged parallel to each other; A transfer module according to claim 3 or 4.

6. Each of the first and second upper conveyor belts is mounted on an upper frame portion (46) having a fixed frame portion (46a) and a movable frame portion (46b); the movable frame portion includes first and second distal exit rollers (62a, 62b) defining the distal exit ends of the first and second upper conveyor belts; A transfer module according to any one of claims 3 to 5.

7. the first and second lower conveyor belts and the first and second upper conveyor belts are laterally movable so that the lateral distance between the conveyor belts can be modified. A transfer module according to any one of claims 2 to 6.

8. the first and second lower conveyor belts and the first and second upper conveyor belts are guided by displaceable compensation rollers (39a, 39b) located on the fixed frame parts of the upper frame part (46) and the lower frame part (45); the displaceable compensation rollers are configured to change the travel paths of the first and second lower conveyor belts and the first and second upper conveyor belts to modify their contact lengths with the folding box. The transfer module of claim 6.

9. A support surface (S) in the transfer module is positioned between the upper and lower conveyors (36, 38); the support surface is inclined upwards in the conveying direction at an angle ranging from 1° to 15°, preferably between 3° and 7°, most preferably 5°; A transfer module according to any one of claims 1 to 8.

10. A transfer and stacking assembly for a folding and gluing machine, comprising: The transfer module according to any one of claims 1 to 9; a stacker module (28); The stacker module includes a loading surface (90) and an ejector (76); The loading surface (90) is inclined upwardly in the conveying direction. A transport and stacking assembly comprising:

11. the support surface in the transfer module and the loading surface in the stacker module have substantially the same inclination; A transport and stacking assembly according to claim 10 when dependent on claim 9.

12. at least a portion of the ejector is positioned upstream of the distal exit rollers (65a, 65b) of the first and second lower conveyor belts (38a, 38b); A transport and stacking assembly according to claim 10 when dependent on claim 6.

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