HK1107070A - Apparatus and method for conveying of sheets - Google Patents

Description

The invention relates to a device for conveying arched objects, in particular printed sheets, from an arched object processing machine, in particular an arched printing machine, by which the conveyed arched objects can be conveyed by various conveyor paths, in particular by means of different storage stacks at the ends of which the objects are placed in different storage stacks.

In the field of arc-processing machines, for example, arc printing machines have been used worldwide for many years to print different materials using different printing methods such as offset printing, deep printing, flex printing, etc. In particular, for high-pressure and/or thick materials, it is necessary to ensure a continuous material flow through a printing machine so that the printed sheets are deposited on piles after their printing without stopping the printing machine or the printing process.

For this purpose, chain conveyors are used, which have a circular chain with several handles on which a bow can be held at one edge to carry the bow with the circular chain.

Such devices are known, for example, from DE 24 30 212, which describes a sorting device which allows faulty printed sheets to be sorted from a normal conveyor to a dump pile via an alternative conveyor to another dump pile instead of a normal conveyor. The printed sheets are conveyed from a first circulating chain conveyor to a first dump pile. Along the conveyor path of the sheets of the first chain conveyor, an optional switchable withdrawal drum is placed which takes the printed sheets from the grips of the first chain conveyor and leads them to a second conveyor, if the printer has not found a suitable color density, the sheets are introduced via a second conveyor to a second conveyor.

DE 103 29 833 also describes a bow-laying device whereby the printed bows are carried by a single chain conveyor with several handles to the following storage positions where the bows can be laid at any one of them.

In the first storage position, the arc guiding device is e.g. run as a mechanical switch to remove spotting or sample arcs from the chain conveyor and transfer them to a first storage position.

The disadvantage of the devices used so far is that, in addition to a conveyor, additional guides for the printed arcs must always be available, since the arcs would otherwise hang down on the chain conveyors used.

Conductive elements such as rods or rollers can prevent this, but they are additional construction measures and can also scratch the back of the sheets already printed.

It is also unfavourable that the function of a mechanical switch as a separate device must be integrated into a conveyor to achieve a diversion of the conveyed arcs.

The purpose of the invention is to create a device for conveying arched objects which overcomes the above disadvantages and which allows the creation of at least two different alternating conveying paths, e.g. to fill different output stacks with arched objects, without stopping the work process of the arch-processing machine, e.g. a printing machine, so that the machine can work continuously. The purpose of the invention is to continue to ensure the practicability and accessibility of dry equipment on arch-pressing machines.

This task is solved by a device comprising at least one conveyor module, which has at least one continuous-circulating suction strip, which exerts a downward pressure on the bottom of an object to be conveyed and conveys the object from the beginning to the end of the conveyor module, with at least one conveyor module trained as a mechanical switch to divert a conveyed arched object along its conveyor path.

For the purposes of the invention, suction tape means a conveyor belt by means of which an underpressure can be applied to an arched object through openings in the surface of the belt so that the object is sucked to the surface of the conveyor belt. For this purpose, for example, a conveyor belt with passing openings can be led at least partially through a chamber open to the conveyor belt closely below, in which an underpressure is generated so that air is sucked into the chamber through the openings in the conveyor belt. Alternative designs are also possible to realize a suction belt within the meaning of the invention.

The main idea of the invention is that instead of a chain conveyor with handles for conveying the arched objects and still needing guides, the conveyor is now, according to the invention, carried by at least a suction strip, which, on the one hand, by the suction effect holds the objects to be conveyed and, on the other hand, also supports the objects so that they cannot hang through.

Furthermore, it is essential to the invention that the transport of objects is by means of at least one conveyor module, preferably by means of several conveyor modules arranged in succession in the conveyor direction. At least one conveyor module, preferably all have at least one suction belt for transporting the objects and at least one conveyor module is designed to act as a mechanical switch, by which an object to be transported is guided along at least two different conveyor paths. Depending on the number of switches, many different conveyor paths can be realized.

In this case, a conveyor may consist of several conveyor modules in a preferred design of the invention.

In the case of an application of the invention in connection with printing machines, such a device may be used, for example, to direct printed sheets from a printing machine to different stacks of sheets, e.g. to enable continuous printing operation.

In a preferred design of the invention, it may be provided that a conveyor module forming a switch may occupy at least two mechanical positions to guide conveyed arched objects along at least two conveyor paths, for example by switching between these positions via a master control, for example, to achieve a change in a conveyor path, the end of the conveyor module acting as a switch may be moved relative to the beginning of the subsequent conveyor module.

In particular, if the beginning (in the direction of conveyance) of a conveyor module is fixed, a displacement of the end of this conveyor module can be easily made during a conveyor operation, since even during the switching period objects can continue to be routed to the conveyor module, e.g. directly from a machine processing the arched objects or from a previous conveyor module.

By moving the end of a conveyor module, this end can be positioned in front of the beginning of at least two alternative conveyor paths, which may be given, for example, by the respective beginning of at least two other conveyor modules, in order to transfer a conveyed object to another conveyor path or to another conveyor module.

According to the invention, it may be envisaged that a conveyor system consists at least in part of at least two conveyor modules between which an arched object, in particular a seamless one, can be passed.

A conveyor module which forms a pivot may be rotatably stored around a pivot axle and may be switched to individual pivot positions at any one of them, with an alternative conveyor path connecting at each pivot position.

In principle, the structure of a conveyor module is such that at least one suction strip circulates endlessly and the area between two diversion positions at the beginning and end of a conveyor module defines the conveyor path.

In a preferred design, a conveyor module may have several parallel, in particular spaced, suction belts. For example, the spaced suction belts may be guided over spaced rolls, with the rolls at the beginning/end of a conveyor module all arranged on a rotating axis. Each roll may have its own rotating axis or all the rolls may be arranged at a rotating position on a common rotating axis.

A preferred design may provide for a conveyor path to be extended over adjacent conveyor modules, whereby a transfer of a conveyor object can be carried out in a particularly safe and particularly tangential manner between two conveyor modules, if the conveyor coils are arranged at the beginning/end of a conveyor module between the conveyor coils at the end/beginning of a conveyor module. This is possible if, as mentioned above, the individual conveyor coils at a conveyor position of a conveyor unit are spaced, in which case the conveyor coils of another conveyor module are located. Thus, a collision between two adjacent conveyor modules may occur.

In such a connection, for example, the transformer coils at the beginning/end of two adjacent conveyor modules may have a common axle, and the transformer coils at the beginning/end of the conveyor modules may have separate parallel axles with separate or even a common axle.

An example of the invention is shown in the following figures. Figure 1:A view of a conveyor with a switch in a first positionFigure 2:A view of a conveyor with a switch in a second positionFigure 3:the transition between two conveyor modules with a common rotation axis at the outgoing coilsFigure 4:the transition between two conveyor modules with separate rotation axis at the outgoing coilsFigure 5:two conveyor modules with a control device arranged between themFigure 6 :a device for taking samples in the inclined stateFigure 7 :a device for taking samples in the inclined state

The following figures illustrate the application of the device of the invention to a sheet-printing machine, but the characteristics described below may be applied to conveyor devices for any application.

Figure 1 shows the schematic design of a device of the invention for conveying arched objects, e.g. sheets of a printing machine, which essentially comprises four conveyor modules 1, 2, 3, 4 in this version. The printed sheets 200 are deposited on the first conveyor module 1 in the conveyor direction by means of a transmission system, e.g. a known chain-grapple system, after the last printing operation of a printing machine not shown, by means of a transmission system not shown, and there on the conveyor belts 10 which maintain the 200 sheets by means of pressure.

In another version, the suction valves 11 of the respective conveyor modules 1, 2, 3, 4 can operate independently of each other and can be driven by separate drives not shown, which makes it possible to change the distance of the printed sheets 200 from each other by having different conveyor belt speeds for each successive conveyor module, thus optimizing time-critical processes, for example during the transfer process of the conveyor path of the arcs, e.g. in this version from the storage stack 5 to the storage stack 6 or vice versa.

The structure of such suction bands 11 is known to the professional and is not intended to be described here.

Above the conveyor belts 10 of conveyor module 1 additional drying devices 100 may be fitted to fix or harden the inks applied during the printing process in the pre-pressed machine.

The advantage is that, depending on the application and requirements, drying systems of different types can be used here, since there are no structural constraints as with the conventional design mentioned at the beginning. Since drying systems, such as UV dryers, also emit a significant amount of heat which can lead to unacceptable heating of machine parts or even to deformation or damage of the arcs 200, it may be envisaged to make the inner area of the endless closed conveyor belts 10 as a cooling device, e.g. as a cooling unit 15 connected to a separate non-shown cooling unit over sections 16 and 17.

This ensures that a sheet 200 is cooled from the back while passing through the drying equipment 100 and that the suction tapes 11 themselves are cooled, which, in the absence of a printed sheet, can be irradiated, for example, by the UV dryer and would otherwise overheat uncontrollably or even be destroyed.

Furthermore, the mechanical parts of the conveyor system may not overheat, which may lead to malfunction of the machinery or even to a danger to the operator.

The conveyor module 2 following conveyor module 1 is herein designed as a mechanical switch according to the invention to supply the printed sheets 200 to a first conveyor to a first conveyor stack 5 or to a second conveyor to a second conveyor to a second conveyor stack 6 by means of a first conveyor route, where the first conveyor route is essentially formed by the following conveyor module 3 and the second conveyor route by the conveyor module 4.

To this end, the conveyor belt 10a or the conveyor end of conveyor module 2 in the conveyor direction, and in particular the entire conveyor module, is moved to one of the two positions 8 or 9 in order to convey the printed sheets 200 either via the downstream conveyor module 3 to the first conveyor stack 5 or via the downstream conveyor module 4 to the second conveyor stack 6. Figure 1 shows the conveyor module 2 in position 8, which leads the printed sheets 200 to conveyor module 3 and from there to the storage stack 5.

Figure 2 shows the conveyor module 2 in position 9, whereby the printed sheets 200 are directed to conveyor module 4 and from there to the storage stack 6.The switch between the two alternative conveyor paths, i.e. either conveyor module 3 or conveyor module 4, is made by shifting the conveyor module 2's end in conveyor direction around the axis 19 given by the shaft around which the conveyor belts 10,11 rotate.

The transmission of the sheets 200 between the respective conveyor modules 1, 2, 3, 4 can be carried out seamlessly, for example, by arranging the individual suction bands 11, 11a of adjacent conveyor modules, of which one conveyor module may have several parallels, in the direction of the arc, so that a coupling of adjacent conveyor modules results, which results in a transmission of the sheets 200 seamlessly during the transmission from one conveyor module to the next conveyor module and is continuously held by the suction action of the suction bands.

The rearrangement of the individual suction bands 11 and 11a of adjacent conveyor modules may be such, for example, as shown in Figure 3, that the respective rolling coils 300 and 300a at the end and beginning of the adjacent conveyor modules are on a common geometric axis 19, without the need for the axis 19 to be formed by a common mechanical shaft.

In particular, when the transmission module 1 is switched to the transmission module 2, the common axes 19 and 19a may be identical and be formed by the common shaft 20 which then forms the shaft around which the transmission module 2 can be rotated to move its end to the two positions 8 and 9 respectively.

Alternatively, as shown in Figure 4, a transfer may be made by partial displacement or interlocking of the 300 and 300a rolls of adjacent suction belts 11 and 11a, depending on the design and requirements, whereby the axles 19 and 19a of the 300 and 300a rolls of the respective suction belts 11 and 11a are parallel to each other and preferably as close together as possible to allow a nearly seamless transfer of the 200 sheets between the conveyor modules.

In both of the above versions, the interconnection of the transverse coils 300 and 300a of adjacent conveyor modules is achieved by having several parallel suction belts 11 and 11a, respectively, running over several transverse coils 300 and 300a on a single shaft or separate shafts, respectively, with the transverse coils of a conveyor element spaced in the direction of the transverse coils of an adjacent conveyor element.

In another embodiment, as shown in Figure 5, a control device 30 may be placed between adjacent conveyor modules, e.g. conveyor modules 1 and 2, which can be operated as a draw-down or pull-out machine at a speed independent or synchronized with any of the adjacent conveyor modules.

In a first embodiment, the suction belts 11 and 11a of conveyor modules 1 and 2 are driven by a common shaft 20 on which the rolls 300 and 300a are fixed and which simultaneously act as drive rollers, so that no change in speed or slip is transferred to the shaft when the 200 arcs are transferred from conveyor module 1 to conveyor module 2.

In order to facilitate the transfer of particularly rigid materials, provision may be made for a control device 30 in the area of axles 19 and 19a above suction bands 11 and 11a, which allows the 200-arms to be pressed to the following suction bands 11a and thus to provide the holding effect.

The guides 30 may be made of guide plates, guide rods or guide rollers, or of a running or driven type. e guides 30 are particularly useful for short arcs if they are designed as an intake or an exhaust system, thus compensating for any inadequate force of the vacuum-charged suction belts in the transfer areas between the respective conveyor modules and thus ensuring safe transport of the arcs.

The functional sequence is described in the following terms. After the sheets 200 have been printed on a pre-pressed non-exposed arc press, the printed sheets 200 are deposited on the suction strip 11 of the first conveyor module 1 by means of an un-exposed chain outlet, with the same conveyor speed and the suction strip 11 of the conveyor module 1 working in sync with each other.

During the filling of the pile 5 the upper working level of the pile 5 is kept at a substantially constant height by measuring the working level via sensor devices 51 and lowering the bow pile continuously or in steps by means of an unspecified hood device to allow the safe laying of the sheets 200 on the pile 5.

It switches the conveyor module 2 running as a mechanical switch in the time between two consecutive arcs 200 from position 8 to position 9 so that the subsequent arcs 200 are deposited on the storage stack 6 via the conveyor module 4. The switching may be done, depending on the running of the conveyor module 2, for example by means of one or more pneumatic cylinders not shown or by means of electric motors.

The newly filled storage stack 5 is indicated to the operator by the controller audibly and/or visually, so that the operator can remove the storage stack 5 from its position by means of a suitable lift and replace it with an empty carrier. Once the storage stack 5 has been replaced, the lower storage area of the empty storage stack 5 is driven to the above working level with the said hood device and is now available for refilling. This condition is detected by sensors 50 and 51 and, where appropriate, by additional sensors and transmitted to the above control.

After reaching the maximum stack height in stack 6, the conveyor module 2 switches back to position 8 so that the 200 sheets are now again directed via conveyor module 3 to stack 5. If the replacement of the filled stack 5 with an empty stack 5 is not completed within the time limit for filling the stack 6, the master control shall not give a release signal to the conveyor module 2 to switch the workstations and the whole system shall be stopped.

In this case, however, as the maximum height of the storage heap 6 may be higher than the maximum height of the storage heap 5 due to the design, it may be appropriate to make the storage heap 52 moveable in height to achieve either equal or different heights of the storage heaps 5 and 6.

To ensure continuous production, an initial embodiment of the invention may provide that conveyor units 1, 2, 3, 4 run continuously at a synchronized speed to each other and to the forward-loaded printing press.

In a second embodiment of the invention, it may be provided that the speeds of the individual conveyor modules 1, 2, 3, 4 are different from each other and different from the speed of the printing machine, for example, to vary the spacing of the printed arcs from one another depending on the conveyor module under consideration.

This allows time-critical processes such as the transfer of the conveyor from position 8 to position 9 in conveyor module 2 to be optimized. For example, if the spacing of successive arcs 200 is increased by a higher speed of conveyor module 2 relative to conveyor module 1, more time is available for the transfer of conveyor module 2 between positions 8 and 9, which means increased safety. To allow the transfer of arcs between two successive conveyor modules, provision may be made for the suction belts and their suction effect to be divided into individual sections 90, 91, 90a, 91a, each of which can be loaded with pressure or vacuum independently of each other, as shown in Figure 5.

In addition, it may be envisaged that the control units 30 operated as inlet or outlet units may be run as stand-alone units, the speed of which may be optionally adjusted to the adjacent conveyor modules.

The way it works is, for example, as follows.

For example, if a sheet 200 is on the conveyor module 1 just before the transfer point to conveyor module 2, as shown in Figure 5, the sheet is first held above the vacuum-loaded section 91; during the further transport, the sheet 200 is placed in the conductor 30 which is used as a pull-out device and is now held by it.

At this time, the speed to the control device 30 is equal to the speed of the conveyor module 1. As soon as the shaft 200 is passed through the control device 30 or shortly thereafter, the vacuum is switched off in section 91 of the control module 1 so that the shaft 200 is passed only through the control device 30. While the shaft 200 is being transported through the control device 30, the speed of the control device 30 is aligned with the speed of the control module 2, so that the shaft 200 can be held and held by the suction belts 11a of the control module 2 in section 90a without slipping. Once the shaft 30 is removed, the speed of the control device 30 is re-indicated as 30 of the speed of the control device 30.

To further protect the exposed surfaces of the arcs, it may be appropriate not only to shut off the vacuum in sections 90, 91, 90a, 91a but also to create a slight overpressure over the suction bands so that the arcs float on an air cushion.

A sample-taking output device may also be provided, for example by aiming the conveyor module 2 which is in position 8 at the time considered to position 9 in order to pass one or more samples over the conveyor module 4 and at the same time by placing an additional conveyor 7 above the stack 6 into which the samples fall.

The sampling of the samples is preferably done manually by pressing a button by the operator as long as the button is pressed; alternatively, it may be possible to take a certain number of samples by specifying in the control unit via the control software a number of samples which are automatically stored in box 7 when a button is pressed by the operator.

It may be possible to continue to use the 7th sheet for the deposition of stainless steel sheets. Stainless steel sheets are produced each time the printing machine is started up again until the print image has stabilized, and also when the printing machine is shut down once the dyes are turned off. These sheets do not have the required quality characteristics of the desired print and must be separated. To this end, the stainless steel sheets produced when a printing machine is started up and shut down are automatically transferred to the 7th sheet by storing a freely selectable number of stainless steel sheets in the control software for each start-up and shut-down of the printing machine.

The controller automatically transfers these numbers of spotting sheets to the 7th box when the machine is started or stopped, where they can be manually removed by the operator without interfering with the subsequent production flow.

To this end, the 7 axle is pivoted into the conveyor path of the arched object in a manner similar to that of the conveyor module 2. For this purpose, the 7 axle is designed as a 7a hoist and is rotatable over the shaft 70 and connected, for example, to an unmarked pneumatic cylinder in such a way that when the pneumatic cylinder is actuated, the 7 axle is pivoted from a first resting position 71 as shown in Figure 7 to a second working position 72 as shown in Figure 6. In this position, the 72 incoming arcs are placed in the 7 axle.

When the desired or specified number of sample sheets or stain sheets have been transferred to the 7th tray, the 7th tray is moved back to the resting position 71, where the sample sheets or stain sheets can be easily removed by the operator.

Furthermore, provision may be made for additional conductors 73 to be fitted to the bottom of the fixture 7 to assist the laying of sheets 200 in the fixture 6 stack, if the fixture 7 is in position 71 and the transport of the arched material is carried out via the conveyor module 4 to the fixture 4.

Claims (21)

1. A device for the conveyance of arched objects, in particular printed arcs, whereby arched objects may be conveyed by various conveyor paths, in particular by means of different stacks of storage at the ends of these, characterised by at least one conveyor module (1, 2, 3, 4) having at least one continuous-circulating suction strip (11) which exerts a downward pressure on the bottom of an object to be conveyed (200) and conveys the object (200) from the beginning to the end of the conveyor module (1, 2, 3, 4), whereby at least one conveyor module (2) is trained as a mechanical means of conveying an arched object (200) in its conveyor path.
2. A device according to claim 1, characterised by the ability of a single-way conveyor module (2) to occupy at least two mechanical positions (8, 9) to guide conveyed arc-shaped objects (200) along at least two conveyor paths, in particular by the ability to move the end of this conveyor module (2) relative to the beginning of the subsequent conveyor module (3, 4) in question.
3. Device according to claim 2, characterised by the fact that by moving the end of a conveyor module (2) it is possible to position that end in relation to the beginning of at least two other conveyor modules (3, 4) to pass a conveyor object (200) to another conveyor module (3, 4).
4. Device according to one of the above claims, characterised by a conveyor module (2) forming a switch, which is rotatable around a pivot axis (19, 19a) and can be switched to individual pivot positions (8, 9) as desired, in particular a pivot axis (19, 19a) formed by a pivot axis surrounded by a suction strip (11, 11a).
5. Device according to one of the above claims, characterised by the presence of several parallel, in particular spaced suction bands (11) in a conveyor module (1,2,3,4).
6. Device according to claim 5, characterised by spaced suction belts (11) being passed over spaced rolls (300) with the rolls (300, 300a) at the beginning/end of a conveyor module (1,2) all arranged on a rotating axis (19,19a), in particular on a common rotating axis (20).
7. Device according to claim 6, characterised by the position of the rolling coils (300) at the beginning/end of a conveyor module (1) between the rolling coils (300a) at the end/beginning of an adjacent conveyor module (2).
8. Device according to claim 7, characterised by the fact that the rolling coils (300, 300a) have a common axis (20) at the beginning/end of two adjacent conveyor modules (1, 2).
9. Device according to one of the above claims, characterised by a conveyor module (1) comprising a cooling device (15), in particular a cooling plate, by means of which a suction strip (11) and/or an object (200) lying on it can be cooled.
10. Device according to one of the above claims, characterised by a conveyor module (1,2) divided into at least two functional areas (90, 91, 90a, 91a) at least in its initial/final suction range.
11. Device according to one of the above claims, characterised by a conveyor path consisting at least in area of at least two conveyor modules (1, 2, 3, 4) between which an arched object (200), in particular a seamless one, can be passed.
12. Device according to one of the above requirements, characterised by at least two conveyor modules (1, 2, 3, 4) having separate drives, the speed of which can be adjusted independently.
13. Device according to one of the above claims, characterised by the fact that the respective conveyor units (1, 2, 3, 4) have the same, in particular synchronised conveyor speeds or different speeds, in particular for which the conveyor units have separate drives.
14. Device according to one of the above claims, characterised by at least one guide (30) between two conveyor modules (1, 2, 3, 4) to support the transfer of an arched object (200) between the conveyor modules (1, 2, 3, 4), in particular by means of a guide (30) the conveyor speed of an object (200) between the conveyor modules (1, 2, 3, 4) can be varied, so that the conveyor speed of the guide (30) during a conveyor transfer can be adjusted to the speeds of the adjacent conveyor modules (1, 2, 3, 4).
15. Device according to claim 14, characterised by the variable conveyor speed of a guide device (30).
16. Device according to one of the previous claims 14 or 15, characterised by a guide device (30) being designed as an inlet or an outlet.
17. Device according to one of the above claims, characterised by having a device (7) for taking samples, in particular one which can be tilted into a conveyor.
18. The device described in claim 17 is characterised by the fact that the device (7) for taking samples has additional control devices (73) to support the deposition of the objects being carried (200) in a stack (6) when the device (7) is deflected from the path of transport of the objects (200).
19. A procedure for operating a device according to one of the above requirements, characterised by changing the position of a conveyor module (2) trained as a switch depending on a signal.
20. The method described in claim 19 is characterised by the signal coming from at least one sensor (51, 53) which detects the height of the stack of objects (200) in a storage stack (5,6).
21. A process according to one of the previous claims 19 or 20 characterised by the introduction of a sample-taking device (7) into a transport path in order to automatically take a number of objects (200) into that device (7), in particular when a machine is switched on/off or when a separate requirement is made.