EP4180374B1 - Production line for machining metal sheets - Google Patents

Description

The invention relates to a production line for processing metal sheets according to the preamble of claim 1.

Through the DE 10 2019 118 647 B3 a production line for processing metal sheets is known which has several different machine units, with a transport path of the metal sheets through this production line z. B. is linear, with a metal printing machine and / or a painting machine and / or a loading station and / or a dryer and / or an unloading station being provided as machine units in the transport direction of metal sheets to be processed, with at least two machine units each having at least one transport device for transport have at least one metal sheet resting individually on a transport plane, the transport device of the loading station having a wire frame that lifts a metal sheet, this wire frame being designed in such a way that it moves the transport plane of the metal sheets in a circle around an axis of rotation extending transversely to the transport direction of the metal sheets to be transported an area in which a metal sheet is fed to the loading station, passes through from bottom to top. DE9421974 , EP3896018 , DE102020111752 and US3880272 reveal sheet metal processing machines

Through the US 3,880,272 A a production line for processing metal sheets with the features of the preamble of claim 1 is known.

The invention is based on the object of creating a production line for processing metal sheets, whereby in a mass production of metal sheets with a production speed of several thousand metal sheets per hour, their trouble-free individual transport through the production line is ensured.

The object is achieved according to the invention by the features of claim 1. The dependent claims relate to advantageous refinements and/or further developments of the solution found.

The advantages that can be achieved with the invention are, in particular, that in a mass production of metal sheets with a production speed of several thousand metal sheets per hour, their trouble-free individual transport through the production line, for example. B. is ensured by monitoring the synchronization point and / or without unintentional accretion and / or tilting or snagging of successively transported metal sheets.

An exemplary embodiment of the invention is shown in the drawings and is described in more detail below, which shows even further advantages of the solution found.

Fig. 1

eine Produktionslinie zum Bearbeiten von Blechtafeln mit mehreren Maschineneinheiten;

Fig. 2

eine Blechtafel;

Fig. 3

eine Draufsicht auf eine Transportvorrichtung;

Fig. 4

die Transportvorrichtung in einer perspektivischen Darstellung;

Fig. 5

eine vergrößerte Darstellung der Transportvorrichtung;

Fig. 6

eine perspektivische Darstellung einer Beladestation mit einem vorgeordneten Transportmodul;

Fig. 7

eine Draufsicht auf die Beladestation der Fig. 6;

Fig. 8

eine Draufsicht auf eine Entladestation;

Fig. 9

eine Skizze von einer in einer Beladestation ausgebildeten Anordnung von getaktet betriebenen Düsen;

Fig. 10

eine Skizze von einer Steuerung zur Überwachung und/oder Einstellung eines Synchronpunktes an einer Beladestation;

Fig. 11

eine ein Anheben eines Drahtrahmens unterstützende Hebeeinrichtung mittels Druckluftdüsen und/oder Elektromagneten;

Fig. 12

eine ein Anheben eines Drahtrahmens unterstützende Hebeeinrichtung mittels eines Nockens;

Fig. 13a, 13b

eine ein Anheben eines Drahtrahmens unterstützende Hebeeinrichtung mittels eines Hebels;

Fig. 14a, 14b

eine ein Anheben eines Drahtrahmens unterstützende Hebeeinrichtung mittels eines Stößels;

Fig. 15

eine Produktionslinie mit am Untertrum eines Zugmittels hängend gekoppelten Drahtrahmen;

Fig. 16

einen Durchlauftrockner mit Zugmitteln in mehreren vertikal übereinander angeordneten horizontalen Ebenen.

Show it:

Fig. 1

a production line for processing metal sheets with several machine units;

Fig. 2

a sheet of metal;

Fig. 3

a top view of a transport device;

Fig. 4

the transport device in a perspective view;

Fig. 5

an enlarged view of the transport device;

Fig. 6

a perspective view of a loading station with an upstream transport module;

Fig. 7

a top view of the loading station Fig. 6 ;

Fig. 8

a top view of an unloading station;

Fig. 9

a sketch of an arrangement of clocked nozzles designed in a loading station;

Fig. 10

a sketch of a control for monitoring and/or setting a synchronization point at a loading station;

Fig. 11

a lifting device supporting lifting of a wire frame by means of compressed air nozzles and/or electromagnets;

Fig. 12

a lifting device supporting lifting of a wire frame by means of a cam;

Fig. 13a, 13b

a lifting device supporting lifting of a wire frame by means of a lever;

Fig. 14a, 14b

a lifting device supporting lifting of a wire frame by means of a ram;

Fig. 15

a production line with wire frames suspended from the lower strand of a traction device;

Fig. 16

a continuous dryer with traction devices arranged vertically one above the other arranged horizontal levels.

In industrial metal printing, metal sheets 08 ( Fig. 2 ) usually printed with at least one printed image in a production line 01 by applying at least one printing fluid using a sheet metal printing machine 03 and/or in a sheet metal painting machine 06 z. B. to protect its surface or at least the printed image and/or z. B. painted over the entire surface or partially to create a glossy effect. The metal sheets 08 to be processed in this way have a format, for example. B. between 500 mm × 650 mm and 950 mm × 1,900 mm and each have a sheet thickness of e.g. B. between 0.1 mm and 1.0 mm, preferably between 0.14 mm and 0.5 mm. Depending on their format and material - whether made of tin-plated sheet steel or tin-free sheet steel or made of aluminum - each of these metal sheets 08 can therefore have a mass, for example. B. from a few hundred grams to a few kilograms, e.g. B. from at least 300 grams to five kilograms or more. Particularly in the production of sheet metal packaging, ie in sheet metal packaging printing, sheet metal sheets 08 of this type are mass-produced industrially at a production rate of several thousand sheet metal sheets 08 per hour, e.g. B. at least 6,000 metal sheets 08 are printed and/or painted per hour.

Fig. 1 shows, in a highly simplified schematic representation, an example of such a production line 01 having several machine units for processing metal sheets 08, in which these machine units are arranged one behind the other in a row and work together to carry out a production processing metal sheets 08. So in this production line 01 in the transport direction T of the metal sheets to be processed 08 ( Fig. 2 ) e.g. B. a sheet metal printing machine 03 and / or a sheet metal painting machine 06 is provided, followed by a loading station 02, a continuous dryer 17 and an unloading station 07, in particular the loading station 02 and / or the unloading station 07 each z. B. can interact with a transport module 04 designed as an independent machine unit. The Sheet metal printing machine 03 and the sheet metal painting machine 06 can also be combined in a single machine unit. The machine unit designed as a continuous dryer 17 is z. B. designed as a hot air dryer.

In practice it has been shown that metal sheets 08 transported at a high speed through the production line 01 tend to cause disruptions during their transport, in particular due to friction effects in their respective transport plane and/or due to contamination on their respective transport route. Disturbing friction effects also occur, for example. B. in the event of excessive wear or aging of a belt transport system used to transport the metal sheets 08. Each of these undesirable influences can lead to, for example: B. several metal sheets 08 transported one after the other through the production line 01 unintentionally run into each other and / or become jammed or caught. Metal sheets 08 can also be rotated out of their linear transport path in their respective transport level and thereby z. B. cause a collision with other metal sheets 08 and / or a component of one of the machine units of this production line 01. And even if no collision occurs, despite a constant production speed in the production line 01, at least a free distance between successively transported metal sheets 08, ie the distance between the rear edge of a first metal sheet 08 and the front edge of a next, subsequent second metal sheet 08, can change, like this that a so-called synchronization point shifts, which means that in particular the front edge position of a metal sheet 08 shifts relative to devices arranged in various machine units of the production line 01. By shifting the synchronization point in this way, z. B. in connection with the sheet metal printing machine 03 and / or sheet metal painting machine 06 provided acceleration and / or deceleration processes get out of order, which in particular results in an interaction between machine units linked together in the production process, such as. B. the Sheet metal printing machine 03 or a sheet metal painting machine 06, the at least one transport module 04, the loading station 02, the continuous dryer 17 and the unloading station 07 is disturbed. Such events lead to an undesirable impairment of production and/or damage or even a loss of production due to a malfunction-related machine downtime.

At least the respective transport module 04 and/or the loading station 02 and/or the unloading station 07 each have at least one of their own transport device 09 ( Fig. 3 ) for the transport of the metal sheets 08. A transport route through this production line 01 is e.g. B. linear. At least the machine units designed as a loading station 02 or as a continuous dryer 17 or as an unloading station 07 and arranged one behind the other in the transport direction T of the metal sheets 08 are linked to one another by at least one common traction device 29 which runs through these machine units and is intended for the transport of the metal sheets 08 ( Fig. 1 ), e.g. B. by at least one rotating chain. The direction of rotation of the traction means 29 is in the Fig. 1 indicated by directional arrows. In a preferred embodiment, the traction means 29 is formed by two mirror-inverted chains, these chains extending over several, e.g. B. two shafts 31 each having gears are driven synchronously by a drive 32 designed in particular as an electric motor. Two of these shafts 31 are arranged at least at the two deflection points of the chains, that is to say each at the ends of the transport route spanned by these chains through the production line 01. Rails 33 are preferably arranged in the continuous dryer 17, with each of these chains extending over laterally mounted rollers 36 supported on one of these rails 33.

Fig. 2 shows an example of a rectangular, generally flexible metal sheet 08, a large number of which are to be transported one after the other along the transport path leading through the production line 01. Each of these metal sheets 08 has the for them The intended transport direction T each has a length L and a width B transverse to this transport direction T, the format of the respective metal sheet 08 being defined by specifying its length L times its width B.

Fig. 3 shows, in a top view, an example of one of the transport devices 09 arranged in at least two different machine units of the production line 01. Fig. 4 shows a perspective view of one of these transport devices 09, such as this. B. is arranged in the transport module 04.

Fig. 5 shows the transport device 09 in a top view in an enlarged view. In a preferred embodiment, the transport device 09 has at least one, preferably two, transport belts 11 only in its central region M, which extends longitudinally to the transport direction T of the metal sheets 08, the transport belt or belts 11 each being z. B. are designed as a flat belt, in particular made of a flexible material, in the form of an endless loop. The z. B. between 1 mm and 5 mm, preferably about 2 mm thick flat belts have a width B11 z. B. between 30 mm and 250 mm, preferably about 40 mm or 80 mm. The z. B. table-shaped transport device 09 preferably has a flat plate 12 arranged in a stationary manner in the transport plane of the metal sheets 08 ( Fig. 4 ), whose width B12, which extends transversely to the transport direction T of the metal sheets 08, is at least as large as the width B of the maximum format of the metal sheets 08 to be transported with the transport device 09. The usually strip-shaped central region M of the transport device 09 extends with its narrow side e.g. B. over a maximum of 60%, preferably over a maximum of 30% of the width B12 of the plate 12 of this transport device 09, in particular over 10% to 20% of the width B12 of the plate 12 of the transport device 09, particularly preferably about 15% of the width B12 of the plate 12 the transport device 09, and extends with its long side longitudinally in the transport direction T of the metal sheets 08 to be transported. The plate 12 of this transport device 09 has a length L12, which is preferably at least as long is as large as the length L of the maximum format of the metal sheets 08 to be transported with the transport device 09.

The respective transport belt 11 of the transport device 09 is preferably arranged on deflection rollers with its respective load strand along the transport plane in such a way that each resting on the respective load strand of the transport belt 11 and on the relevant transport belt 11 z. B. also held metal sheet 08 can be transported relative to the relevant stationary plate 12 along a linear transport route, this transport route z. B. extends at least over the length L12 of the transport device 09. The holding force required to hold a metal sheet 08 resting on the relevant transport belt 11 is carried out, for example. B. by suction, with the required suction z. B. is generated by a suction box arranged below the plate 12 of the transport device 09 in conjunction with a suction pump connected to it. The suction pump is preferably switched on and/or switched off as required or at least can be switched on and/or switched off. Alternatively or additionally, magnetic holding means can also be provided for holding a metal sheet 08 resting on the relevant transport belt 11, which are preferably also switchable. The transport device 09 in question can also have several, e.g. B. have two transport belts 11 each arranged parallel to one another.

In the production line 01, at least two of these transport devices 09 are preferably arranged separately from one another, ie as independent structural units in different machine units, with one of these transport devices 09 being arranged in particular in the loading station 02 or in the unloading station 07. The transport belts 11 of the relevant transport devices 09 are each driven by an electric drive 16 in such a way that transport belts 11 arranged in different transport devices 09 preferably rotate at their respective rotational speeds are synchronized with one another, so that metal sheets 08 transported by these transport belts 11 are each transported at the same linear speed, apart from permissible minor tolerances, these metal sheets 08 being placed on these transport belts 11, for example. B. are held by suction and / or magnetically. The transport of the metal sheets 08 resting on the transport belt 11 takes place in their transport plane, ie in particular with respect to the plate 12 of the transport device 09, each largely floating on an air cushion and is therefore almost friction-free, but at least extremely low-friction and practically slip-free, because the respective Metal sheets 08 are only in contact with the comparatively narrow transport belts 11. The respective electric drive 16 of the relevant transport devices 09 is z. B. each designed as an electric motor and preferably connected at least in terms of data technology to a machine control 34 of the production line 01 that is superordinate to the individual machine units, for example. B. with a control center of this production line 01.

Transport belts 11 arranged in different transport devices 09 are preferably driven by their respective electric drive 16 in such a way that they z. B. rotate continuously, especially in synchronism. Alternatively, these transport belts 11 can also be driven in a clocked manner. It can also be provided that the transport belts 11 have a z. B. in the loading station 02 arranged transport device 09 is preferably clocked by the machine control 34 and / or a sheet metal sheet 08 resting on its transport belt 11 is driven to temporarily brake in its linear speed, whereas the transport belts 11 of a z. B. in the unloading station 07 arranged transport device 09 is preferably clocked by the machine control 34 and / or a sheet metal sheet 08 resting on its transport belt 11 is temporarily accelerated in its linear speed. The synchronous operation of the transport belts 11 arranged in different transport devices 09 and thus, above all, the synchronous operation of the transport belts 11 held by these transport belts Metal sheets 08 are particularly advantageous when the machine units of this production line 01 are ramped up or shut down. For a trouble-free transport of the metal sheets 08 through the production line 01, the synchronous operation of the transport belts 11 arranged in different transport devices 09 and thus also the metal sheets 08, but in particular also at the transitions between the machine units of this production line 01 involved in the production process, must be ensured.

The plate 12 of the transport device 09 in question has a belt-free edge region R1 on both sides of its respective central region M; R2, these edge areas R1; R2 has a width which extends transversely to the transport direction T of the metal sheets 08 and is preferably of the same width and is preferably arranged symmetrically with respect to a longitudinal extent of the transport device 09 in question. At least in the belt-free edge areas R1; R2, e.g. B. but also in the central region M of the relevant transport device 09, at least one nozzle field 13, each with several nozzles 14, is formed. The nozzles 14 arranged there are operated in such a way that, to form the air cushion, blown air is blown from them against the underside of a metal sheet 08 resting on the at least one transport belt 11 of the relevant transport device 09 and held on the relevant transport belt or belts 11. In an advantageous embodiment, at least some of the nozzles 14 of the nozzle fields 13 are z. B. each designed as Venturi nozzles. In the respective nozzle fields 13 z. B. a first subset of individual nozzles 14 and / or a second subset of individual nozzles 14 are each arranged such that the first subset of nozzles 14 directs the blown air obliquely outwards in the transport direction T of the metal sheets 08 at an acute angle, ie in each direction of the nearest edge of the relevant transport device 09 extending along the transport direction T of the metal sheets 08 and / or the second subset of nozzles 14 blow out the blown air vertically upwards.

Fig. 6 shows, by way of example, a perspective view of the loading station 02 arranged in the production line 01 together with a transport module 04 arranged immediately upstream in the transport direction T of the metal sheets 08. In this embodiment variant, both the loading station 02 and the transport module 04 each have their own frame 19; 21, these two machine units being joined together seamlessly, so that the frame 21 of the loading station 02 and the frame 19 of the transport module 04 form a common joint. The transport module 04 has a transport device 09 z. B. with a plate 12, with a metal sheet 08 to be transported in the transport direction T indicated by a directional arrow being shown on the plate 12 in both its largest format and its smallest format. For this purpose, the metal sheet 08 only rests on the transport belt 11, which extends longitudinally in the transport direction T and runs around deflection rollers, and is otherwise kept floating above the plate 12 by an air cushion generated by the nozzles 14. In contrast to the version of the transport module 04 according to Fig. 3 and 4 shows the in the Fig. 6 illustrated embodiment variant of the transport device 09 only has a single transport belt 11 arranged longitudinally in the middle of the plate 12.

Fig. 7 shows a top view of the in the Fig. 6 Loading station 02 shown. The loading station 02 has a transport device 09 for feeding metal sheets 08 lying flat, in particular individually in a transport plane of this transport device 09, to the continuous dryer 17, the loading station 02 having at least one wire frame 22, the respective wire frame 22 usually . Can be pivoted in a circle about an axis of rotation 23 which extends transversely to the transport direction T of the metal sheets 08 to be transported. Each of the wire frames 22 is designed in such a way that it passes through the transport plane of the metal sheets 08 lying flat therein in a pivoting movement from bottom to top and with this pivoting movement a flat lying one passes through the continuous dryer 17 transporting metal sheet 08 is erected vertically from its previous transport level. In the preferred embodiment of the loading station 02, two z. B. clocked and braking driven transport belts 11 arranged, which z. B. hold a metal sheet 08 lying flat on this transport belt 11 by suction and / or a magnetic holding force and a sheet metal sheet 08 lying flat e.g. B. up to a stop 24 extending transversely to the transport direction T of the metal sheets 08 to be transported, this stop 24 z. B. is formed by rubber buffers arranged on the rotation axis 23. The transport device 09 of the loading station 02 preferably also has - as before in connection with the Fig. 5 described - two belt-free edge areas R1; R2, in each of which a nozzle field 13 is formed. In the respective nozzle fields 13, several nozzles 14 are arranged to form an air cushion carrying a metal sheet 08 lying flat on the transport belt 11, of which z. B. ejects a first portion of blown air in the transport direction T of the metal sheets 08 at an acute angle, directed obliquely outwards and / or z. B. a second portion of blown air is blown out vertically upwards towards the underside of a metal sheet 08 resting on the transport belt 11. On the respective wire frame 22 there are z. B. arranged laterally in the direction of the nearest edge of the relevant transport device 09 extending along the transport direction T of the metal sheets 08. Arms 26 are arranged, each of which extends into one of the edge regions R1; Grab the recess 27 made in R2. In order to avoid hooking of the metal sheets 08 to be transported by the transport device 09, these recesses 27 preferably have a bevel 28 which runs at an acute angle against the transport direction T of the metal sheets 08 in the direction of the nearest edge of the transport device 09 in question, which extends along the transport direction T of the metal sheets 08 e.g. B. in the form of at least one correspondingly extending edge.

Fig. 8 shows an example of a top view of one arranged in the production line 01 Unloading station 07. The transport device 09 of the unloading station 07 is constructed similarly to the transport device 09 of the loading station 02, so that the same reference numbers are used below for the same components. The unloading station 07 also has at least one wire frame 22, the respective wire frame 22 generally being pivotable in a circle around an axis of rotation 23 extending transversely to the transport direction T of the metal sheets 08 to be transported, each of the wire frames 22 being designed in such a way that it is Transport plane of the metal sheets 08 to be transported with the transport device 09 passes through in a pivoting movement from top to bottom and with this pivoting movement one of the metal sheets 08 transported vertically upright through the continuous dryer 17 is placed flat in the transport plane of the transport device 09 of the unloading station 07. In the preferred embodiment of the unloading station 07, two z. B. arranged in synchronization or clocked and accelerating transport belts 11, which z. B. hold a metal sheet 08 lying flat on this transport belt 11 by suction and / or a magnetic holding force. The transport device 09 of the unloading station 07 preferably also has - as before in connection with the Fig. 5 described - two belt-free edge areas R1; R2, in each of which a nozzle field 13 is formed. In the respective nozzle fields 13, several nozzles 14 are arranged to form an air cushion carrying a metal sheet 08 lying flat on the transport belt 11, of which z. B. ejects a first portion of blown air in the transport direction T of the metal sheets 08 at an acute angle, directed obliquely outwards and / or z. B. a second portion of blown air is blown out vertically upwards towards the underside of a metal sheet 08 lying flat on the transport belt 11. On the wire frame 22 there are z. B. arranged laterally in the direction of the nearest edge of the relevant transport device 09 extending along the transport direction T of the metal sheets 08. Arms 26 are arranged, each of which extends into one of the edge regions R1; Grab the recess 27 made in R2. These recesses 27 have to avoid hooking of the transport device 09 Sheet metal sheets 08 to be transported preferably have a bevel 28 running at an acute angle in the transport direction T of the sheet metal sheets 08 in the direction of the nearest edge of the transport device 09 in question, which extends along the transport direction T of the sheet metal sheets 08, for example. B. in the form of at least one correspondingly extending edge.

In summary, there is a production line 01 for processing metal sheets 08, this production line 01 having several different machine units, at least one of these machine units being designed as a continuous dryer 17. The continuous dryer 17 is designed in such a way that metal sheets 08 to be dried pass through this continuous dryer 17 vertically upright and usually at a distance from one another, with the continuous dryer 17 being preceded by a loading station 02 which is lying flat in a transport plane of a transport device 09 and which is vertically erected by the continuous dryer 17 vertically transported metal sheets 08 are arranged downstream of a flat-laying unloading station 07 in a transport plane of a transport device 09. The distance between metal sheets 08 transported vertically upright through the continuous dryer 17 is only a few centimeters, e.g. B. between 1 cm and 5 cm, especially less than 3 cm. At least one printing fluid was previously applied to at least one surface of the metal sheets 08 to be dried in the continuous dryer 17, ie on one or both sides, in at least one machine unit designed as a metal sheet printing machine 03 and/or in at least one machine unit designed as a sheet metal painting machine 06. The printed and/or painted metal sheets 08 are fed to the continuous dryer 17 one after the other, in particular individually, with these metal sheets 08 being erected vertically from their position in the loading station 02, which is otherwise flat in their transport plane in this production line 01, before being fed to the continuous dryer 17. The vertical erection here is e.g. B. an erection of the individual metal sheets 08 previously lying flat in the transport plane of the respective transport device 09 with a tolerance of less than ±30°, preferably less than ±15° in each case to the vertical, this vertical preferably being related to the transport plane of the respective transport device 09. After being transported vertically upright through the continuous dryer 17, the metal sheets 08 are placed flat one after the other in the unloading station 07, in particular individually, in the transport plane of a transport device 09. In the production line 01, in the transport direction T of the metal sheets 08 to be processed, there is also in particular a cooling zone 18 ( Fig. 1 ) e.g. B. designed in the form of a cooling device in order to cool the metal sheets 08, which are strongly heated during their passage through the continuous dryer 17, to a significantly lower temperature.

In the preferred embodiment, at least two machine units of this production line 01 are each in their own frame 19; 21 trained. At least two of these machine units each have at least one transport device 09 for transporting at least one metal sheet 08, each lying flat in the respective transport plane, in particular individually, each of these separately arranged transport devices 09 for transporting the relevant metal sheet 08 each having at least one transport belt 11. The transport belts 11 of the relevant transport devices 09 are each preferably driven by an electric drive 16, in particular in such a way that transport belts 11 arranged in different transport devices 09 are synchronized with one another in their respective rotational speed, so that metal sheets 08 transported by these transport belts 11 are each transported at least almost be transported at the same amount, ie apart from minor permissible tolerances, at the same linear speed. In the transport plane of the metal sheets 08 lying flat on the transport belt 11, an air cushion is preferably formed below these metal sheets 08 and these metal sheets 08 are arranged to float in their transport plane by the air cushion.

In the production line 01, the machine units of the loading station 02, the continuous dryer 17, the cooling zone 18 and the unloading station 07, which are arranged one behind the other in the transport direction of the processed or to be processed metal sheets 08, are always linked to one another, and not only through a functional, ie control-related linking of the relevant ones Transport devices 09, but also physically, ie mechanically by at least one traction device 29 z. provided for the transport of the metal sheets 08. B. in the form of at least one chain running through preferably all of these machine units. The at least one traction means 29 passing through the relevant machine units engages both the pivotable wire frame 22 of the loading station 02 and the pivotable wire frame 22 of the unloading station 07, so that the relevant wire frame 22 is coupled to the traction means 29, the traction means 29 e.g. B. has at least one coupling element 37 ( Fig. 1 ), to which the respective wire frames 22 are attached during coupling. The at least one traction means 29 passing through the relevant machine units is thus designed to engage both the relevant pivotable wire frame 22 of the loading station 02 and the relevant pivotable wire frame 22 of the unloading station 07 and to produce a coupling of the relevant wire frame 22 to the relevant traction means 29. A rotational speed of the traction means 29 passing through the relevant machine units and the respective linear speed of the transport belts 11 transporting the metal sheets 08 in the respective transport devices 09 of the production line 01 are in particular coordinated with one another by the machine control 34, in particular synchronized with one another.

Especially at a high production speed of several thousand metal sheets 08 per hour, e.g. B. of at least 6,000 metal sheets 08 per hour, and / or with a large format of the metal sheets 08 to be processed in the production line 01 of z. B. more than 700 mm x 1,000 mm and / or with a small sheet thickness of the metal sheets 08 of z. B. less than 0.3 mm have an effect on the affected areas Sheet metal panels 08 increase acceleration forces at the moment they are lifted by the respective wire frame 22 of the transport device of the loading station 02. These acceleration forces cause, under the aforementioned circumstances, unstable corners of the metal sheets 08, which do not rest on the respective wire frame 22, to bend downwards in the area of the rear edge of the metal sheets 08 raised by the wire frame 22 as a result of the mass moments of inertia of gravity and thus reach the area of the transport path, in particular of a subsequent metal sheet 08. Since the corners of the raised metal sheet 08 are not supported in this area by the respective wire frame 22 of the transport device of the loading station 02, they can therefore sag. This can lead to a collision with the front edge of that sheet metal sheet 08 which immediately follows the sheet metal sheet 08 that is about to be lifted by the respective wire frame 22, with the result that a production interruption and/or a scrap of sheet metal sheets 08 can result in the production line 01.

To avoid this potential malfunction, a production line 01 for processing metal sheets 08 is proposed, which has a metal printing machine 03 and/or a painting machine 06, with a loading station 02 in the transport direction T of the metal sheets 08 after the metal printing machine 03 and/or the painting machine 06 and immediately After the loading station 02, a continuous dryer 17 for drying the printed and / or painted metal sheets 08 are arranged. The loading station 02 has a plurality of wire frames 22 each rotating about a rotation axis 23 extending transversely to the transport direction T of the transported metal sheets 08, these wire frames 22 being arranged one after the other to lift the metal sheets 08 supplied to the loading station 02 lying down, in particular individually, from their transport plane, Each of these wire frames 22 is designed in such a way that it passes through the transport plane of the metal sheets 08 in a circle from bottom to top in an area in which these metal sheets 08 are each fed to the loading station 02, in particular individually, and with this pivoting movement one of the flat lying ones erects metal sheets 08 to be transported through the continuous dryer 17. The loading station 02 also has z. B. in edge regions R1 formed in the transport plane of the metal sheets 08 along their transport direction T; R2 each has at least one nozzle field 13, each with a plurality of nozzles 14, with nozzles 14 arranged there being operated in such a way that blown air is blown from them, preferably vertically upwards, against the underside of a metal sheet 08. At least a subset of the nozzles 14, which preferably blow out the blown air vertically upwards, are operated in a clocked manner, these clocked nozzles 14 being switched on to emit blown air, while the metal sheet 08 in question is taken over and lifted by the wire frame 22, and these nozzles 14 are switched off , before its blown air hits the front edge 46 of that metal sheet 08 which immediately follows the metal sheet 08 that has just been taken over and lifted by the wire frame 22.

Fig. 9 shows, in a simplified sectional view, an arrangement of at least one nozzle 14, each of which is operated in a clocked manner and preferably blows out vertically upwards, in a loading station 02. Preferably, several such nozzles 14 are provided. In the Fig. 9 a wire frame 22 of the transport device of the loading station 02 is shown in three different positions that this wire frame 22 assumes during its pivoting movement about the axis of rotation 23. A sheet metal sheet 08 fed to the loading station 02 is preferably transported in its transport direction T by at least one transport belt 11, on which the sheet metal sheet 08 in question lies flat, until its front edge 46 reaches the stop 24. In particular, at the time when the front edge 46 reaches the stop 24, the metal sheet 08 in question is picked up by the wire frame 22 and pivoted upwards from the transport plane in which the at least one transport belt 11 is located. As a result, the metal sheet 08 in question is preferably at least almost vertically erected from its previous transport level before it is fed to the continuous dryer 17.

In a preferred embodiment, the blowing air nozzles 14, which are preferably blown out vertically upwards, are operated with a blowing pressure whose strength can be adjusted. The strength of the blowing pressure of the nozzles 14, which blow out the blowing air preferably vertically upwards, is z. B. depending on a production speed of the metal sheets 08 to be processed in this production line 01 and / or depending on a format of the metal sheets 08 to be processed in the production line 01 and / or depending on a sheet thickness of the metal sheets 08 to be processed in the production line 01 set or at least adjustable. To adjust the strength of the blowing pressure of the nozzles 14, which preferably blow out the blowing air vertically upwards, a throttle valve 38 is preferably connected on the output side to these nozzles 14 and on the input side to a compressed air source 41, the flow cross section of which is z. B. remotely controlled, especially on a z. B. machine control 34 designed as a control center of this production line 01 can be adjusted, and a pressure gauge 39 is provided.

The blowing air nozzles 14, which preferably blow out vertically upwards, are only switched on to emit blowing air when metal sheets 08 are transported through the production line 01 at a production speed greater than a preset minimum speed. The blowing air is preferably blown out vertically upwards by nozzles 14, for example. B. until a preset minimum value is reached for the production speed of the metal sheets 08 to be processed in this production line 01 and/or for metal sheets 08 with a smaller format than a preset minimum format for the metal sheets 08 to be processed in the production line 01 and/or for metal sheets 08 with a sheet thickness greater than a preset minimum sheet thickness for the sheet metal sheets 08 to be processed in the production line 01. This can ensure that the operating mode of the production line 01 described above is only active when unstable corners of the metal sheets 08 actually bend. This is how one can Malfunction in the production line 01 and/or an interruption of operations and/or a production of scrap metal sheets 08 can be avoided. In addition, the solution described can be used both on a new production line 01 and for retrofitting in a production line 01 that is already in use by a customer.

As already mentioned, even at a constant production speed in production line 01, disturbances such as e.g. B. a changing traction behavior between the respective metal sheet 08 to be transported and the at least one transport belt 11 carrying the metal sheet 08 in question, the free distance between successively transported metal sheets 08, ie the distance between the rear edge of a first metal sheet 08 and the front edge 46 of one of the first Change the metal sheet 08 immediately following the second metal sheet 08, so that the synchronization point shifts, which means in particular that the front edge position of a metal sheet 08 currently fed to the loading station 02 also shifts relative to an end of that wire frame 22 of the transport device of this loading station 02 facing this metal sheet 08 , which is intended to take over the sheet metal sheet 08 that is currently being fed and, due to its pivoting movement, moves into the area in which it is to take over the sheet metal sheet 08 that is currently being fed to the loading station 02. This is because all the metal sheets 08 supplied to the loading station 02 must be taken over one after the other, in particular individually, by one of the several wire frames 22 rotating around the axis of rotation 23 and raised in a timely manner as a result of the pivoting movement of the respective wire frame 22, before a metal sheet 08 immediately following the currently raised metal sheet 08 enters the effective range of another wire frame 22. Otherwise there will be disruptions in the transport of the metal sheets 08 and, as a result, production interruptions in the production line 01.

To avoid this cause of disruption - as shown in the Fig. 10 can be seen - proposed that a first detection device 42 and a second detection device 43 are provided in or on the loading station 02, the first detection device 42 and the second detection device 43 each being connected in terms of signals to a preferably digital control unit 44. The first detection device 42 detects a first time at which one of the wire frames 22 of the transport device of the loading station 02 assumes a specific rotational angular position related to the transport plane of the metal sheets 08, the first detection device 42 sending a first signal representing the detected first time to the control unit 44 . The first detection device 42 can be arranged at different positions in the loading station 02, which is in the Fig. 10 is indicated by a second alternative installation position. The second detection device 43 detects a second time at which the front edge 46 of the metal sheet 08 currently supplied to the loading station 02 reaches a certain position, this position in the transport plane of this metal sheet 08 in the transport direction T of this metal sheet 08 in front of an end facing this metal sheet 08 The wire frame 22 provided for taking over this metal sheet 08 lies, the second detection device 43 sending a second signal representing the detected second point in time to the control unit 44. The control unit 44 is designed in such a way that it determines an actual value for a time difference ΔT between the first point in time and the second point in time and compares this actual value with a setpoint value predetermined for the time difference ΔT, preferably stored in the control unit 44, and determines a deviation of the actual value from the setpoint value , whereby the control unit 44 reports a deviation of the actual value from the setpoint value that lies outside permissible tolerance limits and / or on a display device 48 z. B. displayed graphically and/or numerically. This control unit 44 can z. B. also be integrated in the machine control 34 of the production line 01. The first detection device 42 and the second detection device 43 are preferably each designed as a contactless sensor.

In a preferred embodiment, a z. B. designed as an electric motor drive 47 is provided, the control unit 44 being designed to control at least this drive 47 in the event of a deviation of the actual value from the setpoint value that lies outside permissible tolerance limits in such a way that the wire frame 22 which is responsible for taking over a next loading station 02 supplied sheet metal sheet 08 is provided, pivots at such a time into the transport plane of this next sheet metal sheet 08, so that for this next sheet metal sheet 08 the actual value of the time difference ΔT is again within the permissible tolerance limits. The permissible tolerance limits are e.g. B. in the single-digit percentage range from the target value or even below. In a particularly preferred embodiment, the drive 47 pivoting the wire frame 22 about the axis of rotation 23 is identical to the drive 32 driving the traction means 29, the traction means 29 being arranged continuously at least through the loading station 02 and the continuous dryer 17 arranged downstream of it. This latter embodiment is very advantageous if the traction means 29 engages the relevant pivotable wire frame 22 of the loading station 02 and is designed to produce a preferably mechanical coupling of the relevant wire frame 22 to the relevant traction means 29.

The control unit 44 can be designed in such a way that it determines several actual values for a time difference ΔT between the first point in time and the second point in time and sorts out an implausible actual value before comparing the actual values with the setpoint specified for the time difference ΔT. The control unit 44 can also preferably be designed in such a way that it also controls components of the production line upstream of the drive 47, such as. B. the loading station 02 or the painting machine 06 or acts on a virtual drive axis acting on several machine units on the production line.

The solution described makes it easier to set the optimal synchronization point for the inflow of metal sheets 08 to the loading machine 02 when production conditions change. It also helps to avoid a collision of metal sheets 08 with the wire frames 22, which in turn avoids production interruptions and scrap of metal sheets 08. This solution also offers the possibility of retrofitting old systems.

As already explained, a point in the production line 01 that is unfortunately very prone to failure in terms of the production process is located on the loading machine 02, which is located upstream of the continuous dryer 17. Because each of the metal sheets 08 transported through the production line 01 must be taken over in a timely manner at the loading machine 02 by one of the wire frames 22 and be raised before a next metal sheet 08 enters the pivoting range of the wire frame 22. If this is not successful, at least one of the metal sheets 08 following a metal sheet 08 that has just been picked up abuts the end of the wire frame 22 facing the front edge of these metal sheets 08 that has picked up the immediately preceding metal sheet 08. Unfortunately, such a collision and thus a disruption in the production process of this production line 01 can occur even if the synchronization point to the upstream sheet metal printing machine 03 or sheet metal painting machine 06 is optimally set.

At the same time, in the pivoting range of the respective wire frame 22 of the loading machine 02, the comparatively highest forces act on the relevant wire frame 22, each of these wire frames 22 being designed to be flexible due to its delicate construction. As a result of this flexible design of the wire frames 22, it can happen that one of these wire frames 22, which actually rotates about the axis of rotation 23, remains in a position that is in the transport plane of the metal sheets 08 at a time when the relevant wire frame 22 has just taken over a metal sheet 08 fed to the loading machine 02. As already mentioned, a collision between metal sheets 08 and thus a disruption in the production process of this production line 01 can occur.

One reason for the delayed lifting of a metal sheet 08 that has just been picked up by one of the wire frames 22 can be that individual wire frames 22 are slightly bent. There is also a slight play of wire frame 22 in the z. B. coupling element 37, each designed as a receiving hole, on the traction means 29 designed as a transport chain running through the loading machine 02 and the continuous dryer 17 downstream of it, as a result of wear or manufacturing inaccuracies can lead to a delayed lifting of individual wire frames 22. Likewise, small irregularities in the guidance or deflection of the traction means 29 can lead to the wire frames 22 being lifted unevenly and jerkily and individual metal sheets 08 being lifted late as a result. The stated causes of a malfunction become particularly clear when sudden load changes and loads act on the wire frames 22, as is the case due to the additional weight of the metal sheets 08 picked up together with the retroactive acceleration forces on the loading machine 02.

At a high production rate of several thousand metal sheets 08 per hour, e.g. B. of at least 6,000 metal sheets 08 per hour naturally increase, just as with heavy metal sheets 08 with a mass of e.g. B. more than 2 kilograms the forces acting briefly on the wire frames 22 at the time these metal sheets 08 are picked up, which leads to an elastic deformation of the flexible wire frames 22 and subsequently to a mechanical vibration of the wire frames 22. In the worst case, these vibrations can damage the freshly printed and/or painted surface of these metal sheets 08. At the same time, the times available for the loading process shorten at higher speeds, which further increases the problem of deformations of the flexible wire frames 22 and/or vibrations occurring.

In order to improve the functional reliability in the loading machine 02 and thereby ensure that the production line 01 is less prone to failure, it is proposed to provide a lifting device for the wire frame 22 in the loading machine 02. This lifting device has the advantage that it supports the flexible wire frames 22 when lifting a metal sheet 08 that has been taken over and takes over part of the acceleration forces acting on the relevant wire frame 22 and thus at least largely prevents elastic deformation of the wire frames 22 and their mechanical swinging. Such a lifting device contributes to the fact that the weight of the wire frames 22 can be further reduced, which ultimately results in energy savings in the continuous dryer 17.

The lifting device that supports lifting a metal sheet 08 taken over from a wire frame 22 is - as shown in the Fig. 11 visible - in a first version e.g. B. formed by means of clocked compressed air nozzles 49, these compressed air nozzles 49 being arranged in the loading machine 02 below the transport level of a sheet metal sheet 08 that has been fed to the loading machine 02 and are operated in such a way that they lift the underside of the sheet metal sheet 08, preferably vertically upwards blow a short burst of pressure at the moment when the relevant sheet metal sheet 08 is taken over by the relevant wire frame 22. This version of the lifting device does not act directly on the wire frame 22, but only indirectly, but it supports lifting of the relevant sheet metal sheet 08.

A second version of the lifting device is also in the Fig. 11 shown as an example and sees e.g. B. clocked electromagnets 51 arranged just above the transport plane of a tapering metal sheet 08, in particular in the area of at least one Spacer 52, the relevant spacer 52 being arranged at the end of each wire frame 22 facing away from the axis of rotation 23. These electromagnets 51 are switched in a clocked manner by a control unit 53 and support the wire frames 22 by means of a magnetic force that attracts the wire frames 22. These clocked electromagnets 51 could alternatively also be arranged below the transport plane of a tapering metal sheet 08 and have a supporting effect by means of a magnetic force that repels the wire frames 22. The control unit 53 that switches the electromagnets 51 is z. B. integrated in the machine control 34 of the production line 01.

In a third version of the lifting device - as in the Fig. 12 shown as an example - above the transport level of a tapering metal sheet 08 at least one z. B. rotating cam 54 is provided, the relevant cam 54 mechanically lifting the relevant wire frame 22 and the relevant cam 54 being pivoted away cyclically while a metal sheet 08 enters the loading machine 02.

According to one in the Fig. 13a (longitudinal section) and 13b (cross section) as well as the Fig. 14a (Longitudinal section) and 14b (cross section) of the fourth embodiment, each shown only in sketches as an example, the lifting device is designed as a lifting device which is arranged below the transport plane of a tapering metal sheet 08 on the loading machine 02 and which has at least one of the longitudinal rods 59 or longitudinal bars 59 of the Wire frame 22 preferably lifts in a form-fitting manner in the middle area. This lifting device can, for example, be in the form of a cyclically moved lever 57, in particular provided at its free end with a roller 56, which rotates about an axis of rotation 61, preferably in the transport direction T of the metal sheets 08, or a lever 57 which moves obliquely to the underside of the metal sheet 08 to be lifted by the relevant wire frame 22 on its free side End also z. B. with a roller 56 provided with a plunger 58, preferably a cyclic traversal of the lever 57 or the plunger 58 transversely to the transport direction T of the metal sheets 08 is provided in order to To move lever 57 or plunger 58 out of the pivoting range of the subsequent wire frame 22 after lifting the currently raised wire frame 22. The cyclic axial traversal of the lever 57 is in the Fig. 13b indicated by a double arrow. In the 14a and 14b the lifting movement of the plunger 58 is indicated by a double arrow.

A significant advantage of the lifting device mentioned is that the flexible wire frames 22 do not alone have to generate the force to lift the metal sheets 08.

In order to make the transport of the metal sheets 08 even more efficient, in particular through the continuous dryer 17, it is proposed to design the loading station 02 in the described production line 01 for processing metal sheets 08 in such a way that metal sheets 08 fed to it one after the other, in particular individually, in one of several in the Loading station 02 loosely provided wire frame 22 can be arranged, and an endlessly rotating traction means 29 which passes through at least the continuous dryer 17 and has at least one coupling element 37 to be provided, the relevant z. B. designed as a hanging tab coupling element 37 on the relevant one of the metal sheets 08 received wire frame 22 and a coupling of the relevant wire frame 22 with the traction means 29 is designed, in this proposed more efficient embodiment of the production line 01 in the operating state of the run of the wire frame 22 Through the continuous dryer 17, the wire frame 22 in question, which accommodates the sheet metal sheet 08, is coupled hanging on the lower strand of the traction means 29 and is arranged to be supported at its lower end on a support 62, the wire frame 22 arranged in such a hanging and supporting manner being in an inclined position with an angle W in the range is arranged between 10° and 45° from the vertical. The inclination of the hanging and supporting wire frame 22 can be adjusted in its operating state when it passes through the continuous dryer 17 along the transport route through it Continuous dryer 17 can be designed to vary and assume different angles W at different positions on this transport route. The wire frame 22, which is to be coupled hanging on the lower strand of the traction means 29, has z. B. a locating bolt for latching into the hanging tabs of the traction device 29. The support 62 supporting the lower end of the wire frame 22 that accommodates a metal sheet 08 is z. B. as a permanently installed rail or as a support system that rotates preferably synchronously with the traction means 29, for example. B. in the form of a belt. The inclination of the hanging and supporting wire frame 22 ensures the stability of the metal sheets 08 transported in this way, insofar as these metal sheets 08 neither sink nor bulge at the respective inclination. The particularly efficient design of production line 01 proposed here is exemplary Fig. 15 illustrated.

This configuration of the production line 01 has the advantage that, in contrast to wire frames 22 designed to rotate about a rotation axis 23, the wire frames 22 suspended on the lower strand of the traction means 29 can be designed to be very delicate, so that only a very small mass has to be moved, which is the case Operation of production line 01 leads to energy savings. In addition, when transported by means of a wire frame 22 suspended on the lower strand of the traction means 29, the metal sheets 08 supplied to the loading station 02 do not have to be completely transported in their transport speed before they are taken over by the wire frame 22 in question, in contrast to transport by means of a wire frame 22 designed to rotate about an axis of rotation 23 be braked so that the production line 01 can be operated with a higher throughput of metal sheets 08. In addition, wire frames 22 suspended on the lower strand of the traction means 29 reduce the risk that a metal sheet 08 transported by them will stick to the printed and/or painted surface, for example. B. is damaged by vibrations in a contact zone between the relevant metal sheet 08 and wire frame 22.

As already described, the loading station 02 for loading the continuous dryer 17 with the printed and/or painted metal sheets 08 is arranged directly in front of the continuous dryer 17 in the transport direction T of the metal sheets 08. Furthermore, immediately after the continuous dryer 17, an unloading station 07 is preferably arranged for unloading the metal sheets 08 transported through the continuous dryer 17, the unloading station 07 being designed in such a way that it unhooks the relevant wire frame 22 transporting the metal sheet 08 from the lower strand of the traction means 29. Furthermore, in a preferred development, a transport device 63 that is independent of the traction means 29 is provided, this transport device 63 being designed to transport wire frames 22 that are suspended and thus detached from the lower strand of the traction means 29 at the unloading station 07, individually or stacked or shingled, back to the loading station 02. In the Fig. 15 the return transport of the wire frames 22 unhung and unloaded in the unloading station 07 is indicated by directional arrows. In the unloading station 07, the wire frames 22 transported through the continuous dryer 17 are automatically unhooked from the lower strand of the traction means 29 and returned to the loading station 02 by means of the transport device 63. The metal sheets 08 can be placed in the unloading station 07 either with their printed and/or painted surface facing up or down and from there they can be transported further in the production line 01.

The wire frame 22 suspended transporting traction means 29 is z. B. formed by two mirror-inverted chains, these chains being driven synchronously via several shafts 31 each having gear wheels, two of these shafts 31 each being arranged at the ends of the transport route spanned by these chains through the production line 01.

In a particularly efficient design of the production line 01 - as exemplified in the Fig. 16 shown - at least two traction means 29, arranged vertically one above the other, each passing through at least the continuous dryer 17 provided, with these traction means 29 being arranged in different planes, preferably horizontally extending through the relevant continuous dryer 17, and with at least one of these traction means 29 having a support 62 which supports the wire frames 22 suspended from it. In this embodiment of the production line 01, the loading station 02 has a switch 64, this switch 64 being designed to selectively supply metal sheets 08 supplied to the loading station 02 to one of the traction means 29 arranged vertically one above the other. The switch 64 is z. B. arranged upstream of the loading station 02 or formed as part of the loading station 02. The assignments of metal sheets 08 to the individual traction means 29 arranged vertically one above the other that can be carried out by the switch 64 are in the Fig. 16 indicated by arrows. This special design of the continuous dryer 17 with at least two traction means 29 arranged vertically one above the other has the advantage that the length of the transport route through the relevant continuous dryer 17, compared to the design with a traction means 29, in only a single plane passing through the relevant continuous dryer 17, in particular horizontally can be shortened.

Reference symbol list

01

production line

02

loading station

03

Sheet metal printing machine

04

Transport module

05

-

06

Sheet metal painting machine

07

Unloading station

08

Sheet metal

09

Transport device

10

-

11

Transport belt

12

plate

13

Nozzle field

14

jet

15

-

16

drive

17

Continuous dryer

18

Cooling zone

19

frame

20

-

21

frame

22

Wire frame

23

Axis of rotation

24

attack

25

-

26

poor

27

recess

28

bevel

29

traction means

30

-

31

Wave

32

drive

33

rail

34

Machine control

35

-

36

Roller

37

Coupling element

38

Throttle valve

39

manometer

40

-

41

Compressed air source

42

first detection device

43

second detection device

44

Control unit

45

-

46

leading edge

47

drive

48

Display device

49

Compressed air nozzles

50

-

51

Electromagnet

52

Spacers

53

Control unit

54

cam

55

-

56

role

57

lever

58

Pestle

59

longitudinal bar; Longitudinal spar

60

-

61

Axis of rotation

62

edition

63

Transport facility

64

Soft

b

Width

B11

Width

B12

Width

L

length

L12

length

M

midrange

R1; R2

Edge area

T

Transport direction

W

angle

Claims (8)

1. Production line (01) for processing metal sheets (08), comprising a sheet printing machine (03) and/or a coating machine (06), and comprising a continuous dryer (17) for drying the metal sheets (08) printed by the sheet printing machine (03) and/or coated by the coating machine (06), wherein a loading station (02) is arranged immediately upstream of the continuous dryer (17) in the transport direction (T) of the metal sheets (08), wherein the loading station (02) comprises a plurality of wire frames (22), each rotating about an axis of rotation (23) which extends transversely to the transport direction (T) of the transported metal sheets (08), wherein the wire frames (22) are arranged to lift metal sheets (08), which are transported horizontally one after the other, out of their transport plane, wherein each of these wire frames (22) is designed in such a way that it travels in a circle, from the bottom upward, through the transport plane of the metal sheets (08) in a region in which these metal sheets (08) are being fed to the loading station (02), and by this pivoting movement sets upright one of the laid-flat metal sheets (08) that is to be transported through the continuous dryer (17), wherein a lifting device is provided in the loading machine (02) for the wire frames (22) thereof, wherein the lifting device is arranged to aid the lifting of a metal sheet (08) that is being transferred by a wire frame (22), characterized in that the lifting device comprises a plurality of timed compressed air nozzles (49), wherein these compressed air nozzles (49) are arranged in the loading machine (02) below the transport plane of a metal sheet (08) that is being fed to the loading machine (02) and are operated in such a way that they blow vertically upward with a pressure surge against the underside of the metal sheet (08) that is to be lifted by said wire frame (22) at the moment at which said metal sheet (08) is being transferred by said wire frame (22), and/or in that the lifting device comprises electromagnets (51) arranged above or below the transport plane of a metal sheet (08) that is being fed to the loading machine (02), and/or in that the lifting device comprises at least one rotating cam (54) above the transport plane of a metal sheet (08) that is being fed to the loading machine (02), wherein said cam (54) is designed to mechanically lift said wire frame (22), and/or in that the lifting device is designed as a stroke-motion device, wherein the stroke-motion device is arranged below the transport plane of a metal sheet (08) that is being fed to the loading machine (02), wherein this stroke-motion device is designed either in the form of a cyclically moving lever (57), which rotates about an axis of rotation (61), or in the form of a ram (58), which is moved at an angle relative to the underside of the metal sheet (08) that is to be lifted by said wire frame (22).
2. Production line (01) according to claim 1, characterized in that, in the case of the lifting device comprising the electromagnets (51), said wire frame (22) which lifts the metal sheet (08) that is being fed to the loading machine (02) has at least one spacer (52) at its end remote from the axis of rotation (23), wherein the electromagnets (51) above or below the transport plane of the metal sheet (08) that is being fed to the loading machine (02) are arranged in the region of the at least one spacer (52).
3. Production line (01) according to claim 1 or 2, characterized in that, in the case of the lifting device comprising the electromagnets (51), the electromagnets (51) are switched in a timed fashion by a control unit (53).
4. Production line (01) according to claim 1 or 2 or 3, characterized in that, in the case of the lifting device comprising the electromagnets (51), the control unit (53) which switches the electromagnets (51) is designed to be integrated in a machine controller (34) of the production line (01).
5. Production line (01) according to claim 1 or 2 or 3 or 4, characterized in that, in the case of the lifting device comprising the at least one cam (54), said cam (54) is designed to pivot away cyclically while a metal sheet (08) is being fed to the loading machine (02).
6. Production line (01) according to claim 1 or 2 or 3 or 4 or 5, characterized in that, in the case of the lifting device designed as a stroke-motion device, the lever (57) or the ram (58) in each case has a roller (56) at its free end.
7. Production line (01) according to claim 1 or 2 or 3 or 4 or 5 or 6, characterized in that, in the case of the lifting device designed as a stroke-motion device, said wire frame (22) that lifts a metal sheet (08) has at least one longitudinal bar (59) or longitudinal beam (59), wherein the stroke-motion device acts in a form-fitting manner in a central region of said longitudinal bar (59) or longitudinal beam (59) to lift said wire frame (22).
8. Production line (01) according to claim 1 or 2 or 3 or 4 or 5 or 6 or 7, characterized in that, in the case of the lifting device designed as a stroke-motion device arranged below the transport plane, a cyclic traversing of the lever (57) or ram (58) transversely to the transport direction (T) of the metal sheets (08) is provided.

Images