Patent Application
20170157880
The invention relates to a machine and a method for folding and adhesively bonding blanks for the production of folding boxes.
Folding boxes are formed from one or more flat, stamped and pre-scored, or respectively slit blanks by folding, gluing and uprighting. Open basket carriers or OBC bottle carriers (basket-like bottle carriers) are particularly complex folding boxes which are produced from one or two blanks.
There are machines for folding and gluing such folding boxes which transport the blanks at a very rapid speed along fixed former bars which carry out the folds. In the process, the blanks are clamped between conveyor belts. With one machine type, blanks which have fold lines aligned at a right angle relative to each other are passed from a first processing line at which the first folds are carried out to a second processing line aligned 90° thereto at which the second folds are made. With another machine type, the blanks are rotated by 90° on the processing line. Additional blanks may be placed precisely on the blanks passing through when they pass along the processing line.
Misalignments, scrap and processing problems with a significant loss of material can easily occur in the known machines arising from the effect of fixed tools on the blanks traveling by. Given the high throughput speed, the processing lines are long, and the machines require a large floorspace. In addition, the investment costs for these machines are high. They are therefore only used by folding box manufacturers. The folded and glued blanks are packed into boxes, stacked on pallets and transported to the customer which aligns the blanks and fills them with goods. In the meantime, large quantities of the blanks are stored. This is associated with significant logistical effort.
Against this background, the objective of the invention is to provide an alternative machine and an alternative method for folding and gluing blanks for producing the folding boxes.
The objective is achieved with a machine having the features of claim 1. Advantageous embodiments of the machine are specified in the dependent claims.
The machine according to the invention for folding and adhesively bonding blanks for the production of folding boxes has:
The machine according to the invention has workpiece carriers which are moved along the processing line. The blanks are fed to the workpiece carriers, and the folding and gluing processes are carried out on the workpiece carriers. Since the blanks remain on the respective workpiece carriers without being transferred to other transportation systems during the folding and gluing process, a high degree of precision is achieved in the folding and gluing process. This is supported by the active means for holding arranged on the workpiece carriers that securely hold the blanks in specific positions on the workpiece carriers so that they do not slip during folding and gluing. Furthermore, this is supported by the active means for folding arranged on the workpiece carriers which execute the folding processes, wherein the forces exerted on the passing blanks by fixed folding means are avoided. Furthermore, the active means for folding can perform folds on fold lines aligned at a right angle to the direction of transportation of the workpiece carrier (transverse folds) which are impossible with fixed means for folding.
Preferably, the machine has both active means for holding as well as active means for folding which are each arranged on the workpiece carriers. The invention also relates to embodiments in which only active means for holding without active means for folding are arranged on the workpiece carriers. Such embodiments are for example suitable for uses in which the blanks can be folded solely by means of fixed means, or respectively means fixedly arranged on the processing line as, for example is the case with cuboid folding boxes which are only folded along fold lines aligned in the direction of transportation (longitudinal folds) and glued, and are filled by users through the front openings and closed. In this case, the means for folding which are fixedly arranged on the processing line are preferably passive means for folding. Furthermore, the invention relates to embodiments in which only active means for folding without active means for holding are arranged on the workpiece carriers. Such embodiments are for example suitable for uses in which transverse folds must be carried out, and static holding elements on the workpiece carriers are sufficient to hold the blanks in specific positions on the workpiece carriers. This is supported in that the active means for folding arranged on the workpiece carriers act with less force on the blanks while folding than fixed means for folding.
The active means for holding are means that hold the blanks on the workpiece carriers by means of a movable, non-solid or solid medium, such as by means of a gas, by applying an underpressure (vacuum) or overpressure (compressed air), and/or by means of a movable solid element.
The active means for folding are means that fold the blanks by means of a movable, non-solid or solid medium, such as by means of a gas, by applying an underpressure (vacuum) or overpressure (compressed air), and/or by means of a movable solid element. The active means for holding and the active means for folding can be partly or entirely the same means.
Passive means for folding are for example former bars arranged fixedly on the processing line, or other fixed tools. Passive means for holding are for example stop bars arranged on the workpiece carriers, and/or arbors for holding blanks.
The machine is suitable for folding and adhesively bonding blanks for the production of folding boxes of any kind. It is particularly suitable for folding and gluing simple blanks and complex blanks, such as blanks for cuboidal folding boxes and for OBC bottle carriers.
According to one embodiment version, the machine has at least one means for gluing blanks which is fixedly arranged on the processing line and is guided past the blanks on the workpiece carriers. This can be in particular linear, flat or other simple gluings. According to another embodiment version, means are arranged for gluing on the workpiece carriers. This can be advantageous for complex gluing geometries, and/or for performing a plurality of gluing processes on the same blanks.
A combination of both embodiment versions is also possible.
The control means are preferably mechanical control means, or pneumatic control means, or hydraulic control means, or electrical control means, or any combination of the aforementioned control means.
The machine according to the invention is particularly suitable for being used in production processes with small batch sizes due to its high processing reliability, its flexibility with regard to processing different blanks, and its comparatively minimum complexity, and in production processes in which orders with different blanks must be processed in quick succession. The machine can in particular be used by folding box manufacturers. The machine is also suitable for folding and gluing blanks for users who fill the blanks with goods. Transporting unfolded and unglued blanks from the folding box manufacturer to the user and storing these blanks at the user is significantly more economical than transporting and storing folded and glued blanks. After being folded and glued, the folded and glued blanks can either be temporarily stored at the user's, or the user supplies the folded and glued blanks in a continuous production process directly (in-line) to a packaging machine for filling the blanks with goods. For production processes with large batch sizes, a plurality of machines according to the invention can be used sequentially, such as at the folding box manufacturer's or at the user's.
According to one embodiment, a plurality of active means for holding, and a plurality of active means for folding, can be arranged on each workpiece carrier. This is advantageous for the folding and gluing process. According to another embodiment, the control means are designed to separately control each active means for holding, and/or each active means for folding, on each workpiece carrier. During folding, this makes it possible to control a part of the active means for holding so that it releases the part of the blank to be folded, and the rest of the blank is held with another part of the active means for holding so that it retains its position. Furthermore, it is possible to perform a plurality of different folding processes on each workpiece carrier.
According to another embodiment, the active means for holding are selected from the means: Vacuum cup, compressed air nozzle, folding flap, or any combination of a plurality of the aforementioned means.
According to another embodiment, the active means for folding are selected from the means: Folding flap, vacuum cup, compressed air nozzle, cam wheel, linear actuator, or any combination of a plurality of the aforementioned means.
According to another embodiment, the vacuum cups and/or the compressed air nozzles are connected to means for supplying a vacuum and/or compressed air from a fixedly arranged vacuum generator, and/or compressed air generator, to workpieces movable along the processing line. All the vacuum cups, and/or compressed air nozzles can be connected via the supplying means to the same vacuum generator, and/or the same compressed air source. Alternatively, a vacuum generator and/or a compressed air source are arranged on each workpiece carrier and can be driven by the movement of the workpiece carrier.
The vacuum generator is preferably a slide vane rotary vacuum pump, or a diaphragm pump, or another vacuum pump. The compressed air source is preferably a reciprocating compressor, or a screw-type compressor, or another compressor, or a compressed air network.
According to another embodiment, the means for supplying a vacuum, and/or the means for supplying compressed air, have a fixed air channel running parallel to the processing line and connected to the vacuum generator and/or the compressed air source and which, on one side, has an opening that extends along the processing line and is sealingly covered by a parallel belt which runs around at least one tractive means and has holes next to the workpiece carriers which are connected via lines to the vacuum cups and/or the compressed air nozzles on the workpiece carriers. A vacuum, or respectably compressed air, is provided along a processing line through the air channel. The air channel has an opening extending along the processing line. A belt runs parallel to the at least one tractive means, wherein it sealingly covers the opening in the air channel. The vacuum cups and/or the compressed air nozzles on the workpiece carriers are connected via lines to holes in the belt. The vacuum, or respectively compressed air, in the air channel passes through the lines to the vacuum cups, or respectively the compressed air nozzles on the workpiece carriers. The vacuum cups, or respectively compressed air nozzles, are thereby reliably supplied with a vacuum, or respectively compressed air, in an easy and reliable manner.
According to another embodiment, valve means are arranged on the workpiece carriers by means of which the vacuum cups are connected to the means for supplying a vacuum, and/or the compressed air nozzles are connected to the means for supplying compressed air, and the valve means are connected to the control means. By means of the valve means, the control means control the connection of the vacuum cups to the vacuum generator, and/or the compressor air nozzles to the compressed air source. The actuation of the means for holding, and/or the means for folding, is hence controlled by the valve means.
According to another embodiment, the active means for holding, and/or the active means for folding, comprise flaps arranged on the workpiece carriers for clamping and/or folding sections of the blanks, and it means for pivoting the flaps, and the means for pivoting are connected to the control means. By means of the flaps, sections of the blanks can be clamped between the flaps and a bearing surface of the workpiece carrier so that they are held on the workpiece carrier. Alternatively, sections of the blanks can be pivoted by means of the flaps relative to the bearing surface in order to fold these sections against other sections of the blanks which are held on the workpiece carriers.
According to another embodiment, the means for pivoting comprise spring elements that pretension the flaps into a starting position. The flaps can be swung out of the starting position by other means for pivoting. When the other means for pivoting do not act, the flaps are independently moved back into the starting position by the spring elements.
According to another embodiment, the control means have stationary curves, and the active means for holding, and/or the active means for folding are coupled to contacting means for contacting the curves. The contacting means are means for pivoting the flaps. Preferably, the flaps are additionally pretensioned by spring elements into a starting position. The spring elements can press the contacting means against the stationary curves so that the flaps are precisely controlled corresponding to the contour of the stationary curves. Alternatively, the contacting means are guided along the stationary curves which move the contacting means in different directions in order to pivot the flaps back and forth. To this end, a pin of the contacting means for example engages in a groove, the sides of which form the curves.
According to one embodiment, the machine has passive means for holding blanks arranged on the workpiece carriers, and/or at least one passive means fixedly arranged on the processing line for folding blanks on the workpiece carriers.
According to another embodiment, the workpiece carriers have stop bars and/or arbors for holding the blanks. The passive means for holding blanks can be present in addition to or instead of active means for holding blanks. According to another embodiment, the passive means for folding is a former bar arranged on a processing line (also termed a “deflector” or “folding switchpoint”) which is contacted by the blanks held on the workpieces while passing through the processing line. The passive means for folding can be present in addition to or instead of active means for folding.
Another embodiment has active means arranged on the workpiece carriers for folding the blanks along fold lines in a direction perpendicular to the direction of transport, and/or passive means fixedly arranged on the processing line for folding blanks along fold lines in the direction of transport of the workpiece carriers. Preferably, the folds are carried out in a direction perpendicular to the direction of transport by active means for folding. The folds along fold lines in the direction of transport of the workpiece carriers can also be carried out by active means for folding.
It is also always possible to perform the folds along fold lines in the direction perpendicular to the direction of transport by passive means for folding. To this end according to one embodiment, the workpiece carriers are pivotably mounted on a base and are fastened to at least one tractive means. The pivotable workpiece carriers are connected to a drive which is connected to the control means that are designed to control the pivoting of the workpiece carriers into one or the other pivot position. The pivoting movements of the workpiece carriers on the base can for example be controlled by means of curves. When transporting the workpiece carrier along first passive means, the workpiece carrier is in a first pivot position in which the first passive means execute folds on the fold lines running in the direction of transport. Then the workpiece carrier is pivoted 90° into the second pivot position. In the second pivot position, the workpiece carrier passes by second passive means which perform the folds of the blanks on the fold lines running in the direction of transport. Then the workpiece carrier is pivoted back into the first pivot position. In this manner, it is possible to have the passive means fold in the blanks along at least two fold lines oriented at a right angle to each other.
According to one embodiment, at least one pressure roller is fixedly arranged on the processing line and rolls on the folded blanks on the workpiece carriers. By means of the pressure roller, the material is pressed together along the fold lines in order to break the cardboard fibers and complete the folds.
According to another embodiment, the runs of the at least one tractive means are oriented vertically. The processing line can therefore extend over both runs. This enables a particularly space-saving machine design.
According to another embodiment, the components of the machine are arranged in a frame. This makes it easier to install and remove the components, in particular while servicing and converting in order to prepare the machine for processing different blanks. According to one embodiment, the machine has an elongated, vertical frame. This is advantageous for a space-saving machine setup.
According to another embodiment, the at least one magazine and the means for supplying individual blanks are arranged on the side of one run of the tractive means, and the delivery station for delivering folded and glued blanks is arranged on the side of the other run of the tractive means. This embodiment is space-saving and makes it easier to integrate the machine into the processing procedure at the folded box manufacturer's or customer's.
According to another embodiment, the means for removing individual blanks from the stack in the magazine comprises a vacuum system which is designed to draw an individual blank from a stack in the magazine into a transfer position.
According to another embodiment, the means for supplying the removed blanks to one of the workpiece carriers comprises an additional transportation system with at least one additional tractive means running around deflection rollers, wherein another run of the additional tractive means runs by the transfer position, and another run of the additional tractive means runs along a section of the transfer line, drivers are arranged on the additional tractive means, the additional transport system has an additional drive, the vacuum system and the additional drive are connected to the control means which is designed such that the vacuum system is synchronized with the additional drive, and the additional drive is synchronized with the drive such that the vacuum system always positions an individual blank from the magazine in the transfer position between the drivers on the additional tractive means, the at least one additional tractive means entrains the blank held between the drivers, and the blank is supplied to the workpiece carrier via the run extending substantially in the direction of a section of the processing line. The blanks provided by the means for removing in the transfer position are accelerated by the additional transportation system to the speed of the workpiece carriers and supplied thereto. A flawless transfer of the blanks to the workpiece carriers can thereby be achieved.
This embodiment is suitable in particular for supplying blanks for OBC bottle carriers to the workpiece carriers, in particular for supplying a jacket blank for such a bottle carrier.
According to one embodiment, the means for removing individual blanks from the stack in the magazine comprises a pivoting suction unit which always places an individual blank on a delivery table. According to an additional embodiment, the means for supplying the removed blank to one of the workpiece carriers comprises a carriage which is guided in guides along a section of the processing line, and on which an additional pivoting suction unit is arranged which is designed to receive an individual blank from the delivery table when the carriage is arranged in a bottom position and, after a pivoting movement, to supply the blank to a workpiece carrier in a top position of the carriage, wherein the carriage is connected to another drive, the pivoting suction unit is connected to an additional drive, and the additional pivoting suction unit is connected to an additional drive, and the additional drives are connected to the control means which are designed such that, after a blank is placed on the delivery table by the pivoting suction unit, the additional pivoting suction unit receives the blank, and the carriage executes a synchronized movement with one of the workpiece carriers, and the additional pivoting suction unit thereby supplies the blank to the workpiece carrier. A particularly dependable supply of blanks to the workpiece carrier is thereby achieved.
The embodiment is particularly advantageous for supplying an additional blank to the workpiece carrier on which a blank has already been placed. This embodiment is particularly advantageous for supplying blanks to form a middle wall and a grip reenforcement in OBC bottle carriers.
According to another embodiment, the means for supplying have a supply plate on which each blank can be positioned, and the means for supplying have means for transferring the supply plate at a right angle to the run of the transport system by a middle drive that is connected to the control means, and the control means are designed to control the transfer of the supply plate at a right angle toward the workpiece carrier in the last section of supplying each blank to one of the workpiece carriers in order to supply the blank by means of the supply plate to the workpiece carrier. This further improves process reliability.
According to another embodiment, the supply plate is dimensioned such that, when moving at a right angle toward the workpiece carrier, it can move between support means on the workpiece carrier on which a blank can be placed. A folding process can be thereby initiated. The support means on the workpiece carrier can in particular be flaps which are in a starting position.
According to another embodiment, the additional pivoting suction unit comprises means for transferring the blank at a right angle toward the workpiece carrier by an additional drive that is connected to the control means. This further improves process reliability.
According to one embodiment, the control means are designed such that the active means for holding on the workpiece carriers take the blanks from the at least one means for supplying. This further improves process reliability. In particular, vacuum cup on the workpiece carriers can be controlled such that they suction the blanks while supplying.
According to another embodiment, the machine comprises means for uprighting the folded and glued blanks into folding boxes. The uprighted folding boxes can then be directly filled with goods. This embodiment is particularly suitable for use by the user.
Another embodiment relates to the arrangement of a machine according to the invention in front of a machine for combining folded and glued blanks into transport units, or in front of a machine for filling the folded, glued and uprighted blanks with goods. The transport units are for example stacks of folded, glued blanks, or a plurality of such stacks on a pallet.
The objective is also achieved by a method having the features of claim 26.
In the method according to the invention for folding and adhesively bonding blanks for the production of folding boxes:
According to another embodiment, the blanks are pulled off of a stationary stack on the processing line and supplied to the workpiece carriers.
According to another embodiment, each active means for holding, and/or each active means for folding, are controlled separately.
According to another embodiment of the method, the active means for holding securely hold the blanks to the workpiece carriers by means of a vacuum or compressed air, or by clamping, or any combination of a plurality of the aforementioned measures, and/or the active means for folding fold the blanks by means of folding flaps, a vacuum, compressed air, a cam wheel, linear actuator or any combination of a plurality of the aforementioned measures.
According to another embodiment, the vacuum and/or the compressed air is supplied to the active means for holding, and/or the active means for folding, on the workpiece carriers, by a stationary vacuum generator and/or a stationary compressed air source while transporting along the processing line.
According to another embodiment, the active means for holding, and/or each active means for folding, are controlled by contacting stationary curves.
According to another embodiment of the method, while being transported along the processing line, the blanks are held by passive means for holding on the workpiece carriers transported along the processing line, and/or are folded by at least one passive means for folding fixedly arranged on the processing line.
According to another embodiment of the method, active means for folding which are transported along the processing line fold the blanks while being transported along the processing line along fold lines in the direction perpendicular to the direction of transport, and/or passive means for folding which are fixedly arranged on the processing line fold the blanks along fold lines in the direction of transport.
According to another embodiment of the method, the blanks are rotated 90° while being transported along the processing line and are folded by means for folding arranged along the processing line on fold lines offset from each other by 90°.
According to another embodiment of the method, after a fold on a fold line, the blanks are further processed along the fold line by means of a pressure roller that rolls on the blanks and is stationarily arranged on the processing line.
According to another embodiment of the method, the blanks are transported, folded and glued along a vertically oriented processing line.
According to another embodiment of the method, the blanks are first transported upward and then downward after being supplied to the processing line, and are removed from the processing line while being transported downward.
According to another embodiment of the method, the blanks are removed from a magazine by suction and supplied to the processing line.
According to another embodiment of the method, the blanks are uprighted, filled and closed following the processing line.
According to another embodiment of the method, the blanks are stacked in a flat state following the processing line.
According to another embodiment of the method, the blanks are temporarily stored following the processing line, or are uprighted, filled and closed directly after the processing line.
The invention is explained in greater detail below based on the appended drawings of an exemplary embodiment. In the drawings:
According to
The deflection rollers 3 to 5 are each mounted on shafts 9, 10.
A drive which comprises an electric motor 12 and a gearbox 13 drives the bottom shaft 9 on which the two bottom deflection rollers 3, 4 sit.
Workpiece carriers 14 are fastened to the two tractive means 7, 8 at distances from each other. To this end, the tractive means 7, 8 are each securely connected to base parts on which the workpiece carriers 14 are mounted. The base parts are for example crossmembers securely connected to both tractive means 7, 8. The workpiece carriers 14 are removable from the base parts and exchangeable with other workpiece carriers 14 in order to adapt the machine 1 to the blanks to be processed.
The individual parts of the machine 1 are arranged in an elongated, vertical frame 15. Arranged on the front side of the frame is another frame 16 that is connected to the frame 15, yet possesses a lower height than that frame.
The two runs 17, 18, 19, 20 of each tractive means 7, 8 are oriented vertically.
A bottom magazine 21 is mounted in the other frame 16. A stack of blanks 22 (such as jacket sections of an OBC) are stored thereupon at an angle so that the bottom blank 22 in the stack is closest to the transport system 2.
A vacuum system 23 comprising a plurality of vacuum cups 24, 25 is assigned to the bottom magazine 21. These are able to pull off individual blanks 22 from the bottom end of the bottom magazine 21.
Furthermore, the machine 1 comprises means for supplying 26 the blanks 22 removed from the bottom magazine 21 to the workpiece carriers 14. These comprise an additional transport system 27 that has two tractive means 34, 35 which are each guided around three additional deflection rollers 28 to 33. One of the additional deflection rollers 28 to 33 is coupled by means of another gearbox 13.1 to the drive 11 of the transport system 2. The vacuum system 23 is capable of drawing individual blanks 22 out of the stack into a transfer position.
The additional tractive means 34, 35 each has an additional run 36, 37 that runs by the transfer position. Furthermore, they have an additional run 38, 39 which is guided along a section of the transfer line. The additional runs 38, 39 are angled at a sharp angle to the runs 17, 18, and approach the runs 17, 18 upward from below.
Drivers 40, 41 are arranged on the two additional tractive means 34, 35 at set intervals from each other. The distance between the drivers 40, 41 on the additional tractive means 34, 35 is such that just one blank 22 passes between the drivers 40, 41 and is clamped between them.
At the bottom, the additional tractive means 34, 35 are guided over additional deflection rollers 28, 29 with a large radius. At the top, the additional tractive means 34, 35 each run over two adjacently arranged additional deflection rollers 30 to 33 with a small radius.
Furthermore, a top magazine 48 is available for another stack with additional blanks 49 (see
A pivoting suction unit 50 is arranged close to the bottom end of the top magazine 48. Located adjacent thereto is a delivery table 51 on which the pivoting suction unit 50 places individual, additional blanks 49 from the top magazine 48.
Arranged adjacent thereto is a carriage 52 which can be moved up and down along vertical guides 53, 54. An additional gearbox 55 is coupled to the top deflection rollers 5, 6 for moving the carriage 52 up and down.
Arranged on the carriage 52 is an additional pivoting suction unit 55.1 for picking up the individual, additional blanks 49 from the delivery table 51 and swinging them to the workpiece carriers 14 on the adjacent runs 17, 18 of the transport system 2.
In the frame 15, means are available for supplying 56 a vacuum and extend parallel to the tractive means 7, 8 of the transport system 2. The means for supplying 56 a vacuum comprises a fixed air channel 57 that is arranged between the two tractive means 7, 8 and runs parallel thereto (see
The air channel 57 is connected to a vacuum pump.
The workpiece carriers 14 each have a workpiece carrier plate 66 which forms, on the outside, a bearing surface 67 for the blanks 23, 49 (see
The suction openings of the vacuum cups 62 to 65 are in the bearing surface 67 of the workpiece carrier 14.
The flap arms 80 to 83 with the widenings 76 to 79 at the ends serve to clamp and fold blanks 22, 49. On the other side of their pivot axes, the flaps 68 to 71 have contacting means 84, 85, 86, 87 in the form of cams on contact arms.
Furthermore, valve means 88 are arranged on the workpiece carriers. The valve means 88 are preferably preloaded by additional spring means into a closed position or open position. Furthermore, they are connected to additional contacting means so that they can be opened or closed by actuating the additional contacting means.
Curves 89, 90, 91, 92 are fixedly attached to the frame 15. The contacting means 84 to 87 and the additional contacting means are guided along the curves 89 to 92 such that they are actuated by them in order to swing the flaps 68 to 71 up out the position shown in
A means for gluing 95 in the form of a nozzle is fixedly arranged on the processing line 93, 94.
The design of the machine 1 makes it possible to upright, or respectively fold and glue flat, pre-scored, or respectively stamped cardboard boxes. Both individual blanks as well as combinations of a plurality of blanks can be processed. The number of combinable blanks can be increased depending on the length of the processing line (sheen height).
In the following, the features and advantages of different exemplary embodiments of machines according to the invention will be explained.
The basic design of the machine makes it possible to upright and/or glue on a small footprint. The control and infeed side are opposite the product delivery to enable a combination consisting of a plurality of machines to increasing performance (depiction at the end of the description).
In contrast to conventional gluing machines, the machines function in a vertical direction, whereby the smaller necessary footprint is achieved.
The principle of the machine is based on entrained workpiece carriers which hold the products and on which all work steps are performed. Leaving the blank on the respective workpiece carrier ensures that great precision is achieved in the folding and gluing process since the product is not handed over to other transport systems. These processes are supported by folding elements which are arranged such that the products positioned on the workpiece carriers are folded while passing through in a hollow longitudinal direction. All transverse folds are carried out by means of the components on the workpiece carriers.
The cardboard boxes can be glued by various media. Cold glue and hot glue for uncoated cardboard boxes or hot-air for coated cardboard boxes are possible. Clamping or gluing with adhesive strips is also possible using corresponding additional aggregates.
The blanks are supplied to the workpiece carriers (the number fluctuates depending on the length of the vertical transport system) via an angle-adjustable storage magazine with separation and an intermediate conveyor belt.
The blanks are held on the workpiece carrier by a vacuum. The workpiece carriers are moved on a vertically running transport system. During transportation, devices are moved on the workpiece carrier by means of straight edges, or respectively curved segments and springs, in order to carry out folding and clamping. In addition, the formers and guides execute the longitudinal folds. At corresponding positions, additional blanks are transferred to the workpiece carriers which are glued to the first blank or folded into it. The fully processed blanks are delivered at the bottom end of the downward-running section of the transport system.
The cardboard blanks are placed as a stack in a storage magazine that is angled slightly relative to the transport system. This magazine is arranged in front of the machine such that the blanks can be separated while standing and supplied to a continuously circulating driver belt. This driver belt runs in sync with the cycling and speed of the transport system of the workpiece carrier. By means of bellows suction cups, the blanks are removed from the magazine which is provided with retainers and drawn toward the belt provided with drivers into the gap between two drivers. At the end position of the suction cup stroke, the vacuum switches off and thereby releases the blank for the drivers. The blank is then cut off from the suction cup against the existing residual vacuum.
Subsequently, the blank is guided by means of the driver belt around a sufficiently large wheel with an outer guide in order to then travel vertically upwards in the same direction of travel as the workpiece carrier transport system. Once the blank has traveled completely around the wheel, the blank which is now straight is guided against to the workpiece carrier on the transport system and suctioned there by the vacuum cups. After the belt travels briefly parallel to the transport system, the belt is guided away at a slight angle from the transport system before it is again guided toward the magazine around a pair of wheels.
Aligned by the drivers, the blank is now located on the workpiece carrier and held there by at least four vacuum cups. At this point in time, the grippers on the workpiece carrier needed for transverse folds lie against the workpiece carrier by means of spring force and thereby enable a nearly flat seating of the blank. Subsequently, the blank is provided with glue at specific points (hot and/or cold glue depending on the cardboard). Then the second blank supplied from a second magazine is placed on the first blank. Directly before this step, the grippers are lifted, and then form the counter holders for the transverse folding of the blank combination.
The second blank, i.e., the handle reinforcement, is also supplied to the machine while standing by means of a magazine at a slight angle relative to the machine. The blank is separated from the magazine by means of pivoting suction unit and placed on a table. By means of this table, the second blank is supplied to another pivoting suction unit which also holds the blank with suction cups.
This second pivoting suction unit is provided with a counterpressure plate with dimensions chosen so that it fits at a slight distance between the oriented grippers of the workpiece carrier. When the second blank is placed on the first one, this first blank is pushed through the grippers along the groove by the counterpressure plate and then folded at 90° perpendicular to the the direction of travel of the workpiece carrier (punch/die principle).
With the basket blank, the handle reinforcing tab is also pre-folded 90° by a spring-loaded abutment. Directly afterward, the counterpressure plate withdraws from the blank, and the grippers close under spring force. By means of this movement, the transverse fold from 90° to 80° is executed.
To ensure that the blanks on the workpiece carrier do not slip during the transverse folding process, the pivoting suction unit moves upward with the counterpressure plate in sync with the transport system until the counterpressure plate withdraws from the gripper area of the workpiece carrier. At this moment, the movement reverses from upward to downward, and the pivoting suction unit can receive the next blank. To prevent the transverse fold from springing back after the grippers open, the fold is then reinforced by the pressure of a roller applied against the workpiece carrier which rolls spring-loaded over the passing workpiece carrier.
Following the transverse folding, hot, or respectively and/or cold glue is applied to specific surfaces of the blank combination. The subsequent first longitudinal fold is performed by folding straight edges. To this end, one side of the grippers on the workpiece carrier open, and the vacuum is also switched off on one side. At this moment, the blank is lifted off the straight edge on the released side. Subsequently, the blank halves are always still elevated. At approximately 45°, the straightedge is supported by an entrained additional folder to prevent the blank from being compressed and shifted.
Before the workpiece carrier on the transport system runs around the top deflection of the transport system, the folding process is about 80% complete (about 160°) and is finished directly following the deflection. To this end, the two still-gripping grippers of the workpiece carrier are opened briefly in order to allow the blank to be swung in. After the blank surfaces are in contact and the grippers have closed again, they are immediately tightly bonded with each other by means of a press roller. Then hot, or respectively and/or cold glue is again applied in order to completely close the blank by means of another longitudinal fold. The side tab is placed on the blank from the rear by means of a folding straightedge and then passed through a pair of rollers in order to complete the fold and gluing.
The grippers on the workpiece carriers are actuated by means of springs and curve templates. The vacuum is applied to the workpiece carriers through a flat belt with connections which runs on a hollow profile open to the outside. The vacuum workpiece carrier is switched by means of mechanically-actuated vacuum valves in the workpiece carrier. By means of special material pairings, the heat arising from friction between the belt and hollow profile is kept to a tolerable level.
According to an additional embodiment, stop bars, or arbors, or other passive means for holding blanks are arranged on the workpiece carriers.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2013 104 432.6 | Sep 2013 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/070685 | 9/26/2014 | WO | 00 |
