EP2323935B1 - Method and device for transporting flat workpieces - Google Patents

Description

The invention relates to a method for changing the transport direction in a transport device of flat workpieces, in particular hose sections, according to the preamble of claim 1 and a device according to the preamble of claim 5.

Such methods and devices are often used in sack making apparatus in which pieces of tubing are singulated from a tube web which are then further processed into sacks. Often the tube web consists of a fabric tube. The tube web is also understood as a juxtaposition of flat workpieces, which are to be separated. But it is also possible to supply already isolated pieces of hose of the device.

Devices in which the aforementioned devices are used, are known and available for a long time on the market. As a rule, these devices initially comprise a separating device in order to separate a supplied fabric hose, which may also be coated, into hose pieces. These consist of two superimposed material webs, which can each consist of several layers. For this purpose, the tube is advanced cyclically in its longitudinal direction in each case by a length of hose piece in a first transport direction. The feed takes place in the direction of the tube axis. Subsequently, a piece of hose is separated from the hose, so separated. This is usually done with a cutting tool such as a knife. However, other separation methods and the associated facilities are conceivable. Subsequently, each tube piece produced in this way is taken over in the device for changing the transport direction of at least one transfer device. This transfer device is arranged downstream of a transport device, with which the pieces of hose can be brought into the individual processing stations. Transfer device and transport device can be combined to form a single transport device.

After separation, the pieces of hose are no longer transported in the longitudinal direction, but in the transverse direction. By "transverse direction" it is meant that the pieces of tubing are now transportable transversely to their longitudinal extent so as to obtain unimpeded access to both ends of the pieces of tubing in the further steps of making bags.

• In einer fakultativ vorhandenen Vorbruchstation werden Formstempel zur Erzeugung einer Falzlinie auf das Schlauchstück abgesenkt. Auf dieser Falzlinie befinden sich später die Eckeinschläge des geöffneten Schlauchbodens. Die Formstempel können zu diesem Zweck auch beheizt werden.
• In der Bodenöffnungsstation wird zumindest ein Ende eines Schlauchstücks aufgezogen, so dass an diesem aufgezogenen Ende ein Boden angeformt werden kann. Die Eckeinschläge befinden sich auf den Falzlinien des Schlauchstücks. Aufgrund ihrer geometrischen Form wird die Bodenöffnung auch Bodenöffnungsquadrat genannt. Dabei sei angemerkt, dass die Form nicht quadratisch, sondern in den meisten Fällen rechteckig ist. In der Regel werden beide Enden eines Schlauchstücks auf die gleiche Weise bearbeitet.
• In der Ventilzettelstation wird ein Ventilzettel auf den zuvor geöffneten Boden des Schlauchstücks gelegt. Durch den Ventilzettel kann später der fertige Sack mit Hilfe eines geeigneten Füllstutzens befüllt werden.
• In einer so genannten Zulegestation werden Teile der Bodenöffnungen bzw. der Bodenöffnungsquadrate, die so genannten Laschen, beidseitig zur Falzkante hin zurückgefaltet. Dabei können Bereiche dieser Laschen überlappen, und diese überlappenden Bereiche dieser Laschen können miteinander verbunden werden.
• Anschließend wird in der Bodendeckblattstation ein Bodendeckblatt auf der zugefalteten Bodenöffnung befestigt, beispielsweise verschweißt.

In the following, additional individual stations will be listed during bag production and their function will be explained:

• In an optional pre-break station, dies are lowered onto the length of hose to create a fold line. On this fold line are later the corner impacts of the open tube bottom. The dies can also be heated for this purpose.
• In the bottom opening station, at least one end of a piece of hose is pulled open, so that a bottom can be formed on this end being pulled up. The corner stops are located on the fold lines of the hose section. Due to its geometric shape, the bottom opening is also called floor opening square. It should be noted that the shape is not square, but in most cases rectangular. In general, both ends of a piece of hose are processed in the same way.
• In the valve dispensing station, a valve leaflet is placed on the previously opened bottom of the tube piece. Through the valve leaflet, the finished bag can later be filled with the aid of a suitable filler neck.
• In a so-called Zulegestation parts of the bottom openings or the bottom opening squares, the so-called tabs, folded back on both sides of the folded edge. In this case, areas of these tabs can overlap, and these overlapping areas of these tabs can be interconnected.
• Subsequently, in the bottom cover sheet station, a bottom cover sheet is fastened to the folded bottom opening, for example welded.

It should be noted that not all of the enumerated stations must be present in a sack making apparatus. So can be dispensed with a pre-break station. Even ground cover sheets do not always have to be applied to make a sack. Nevertheless, further stations are conceivable.

In the following, a bag making process in machines of the prior art will be briefly explained. Since these machines are constructed on the operating and drive side almost the same to simultaneously edit both ends of the hose piece, will not be discussed in detail in the following description on the various machine pages. A previously separated piece of tubing is fed transversely to its longitudinal axis by means of a suitable means of transport (for example double belt conveyor) to a pre-breaking station. There, a forming die is lowered perpendicular to the transport direction of the hose pieces on the hose pieces. The corner folds of the opened bottom of the sack, which is formed in the subsequent bottom opening station, are later located on the folded edge created in this case. Subsequently, a valve is placed on the open bottom on a bottom opening in the valve dispensing station. Through this valve, the bag is later filled with a suitable filling member. In the following Zulegestation the bottom opening of the bag is folded, so that subsequently in the ground cover sheet station by welding the bottom opening thereof with a bottom cover sheet of the bag is completed.

Particular attention must be paid to the transport device, which holds the pieces of tubing from the support surface onto which the pieces of tubing were discharged, takes over and transversely transported to the longitudinal axes and supplies to the processing stations.

Before a piece of hose can be taken over by a conveyor in the transverse direction on its transverse transport plane, the piece of tubing must first rest with its side region on the transverse transport plane, so that it can be detected by a so-called transfer device, such as a driving shoe. This driver leads the hose piece to a conveyor - for example, a conveyor belt - which then brings the hose piece successively to the individual processing stations.

When pushing out of the hose or the already isolated hose piece on the support surface, it is therefore necessary that it is already partially arranged in the region of the transverse transport plane, so that the hose piece rests on this level already shortly before its takeover.

Due to the design, however, this transport plane often includes interference edges, against which the bag is pushed or pushed. As a result, the bag is compressed, possibly even damaged and a subsequent, proper onward transport of the bag is difficult.

Therefore, in devices of the prior art, height-adjustable bearing surfaces are used (eg see EP 1 375 404 A1 for such a device for deflecting printed products.) During the advancement of the tube, although a large part of the later piece of tubing rests on the support surface. The side edge of the length of tubing, which advances in the following cross-transport, is not supported. However, after the support surface has been lowered, this region of the hose piece lies on the transport plane of the transfer device, so that the hose piece can be transported away. However, this procedure has the consequence that the hose piece can only be advanced again when the now empty support surface has been raised again. This has the consequence that two successive pieces of hose a relatively large distance in the Occupy bag manufacturing facility whose performance is limited.

The object of the present invention is therefore to propose a device for changing the transport direction, which reduces the above-mentioned disadvantages.

According to the invention, this object is solved by the features of the characterizing part of claim 1.

Accordingly, it is provided that a following flat workpiece is advanced at least by a certain distance (Δz), while the workpiece in progress continues to move in the second transport direction (x) by a distance (Δx) which is smaller than the workpiece width (B) is transported.

The workpiece running ahead can now be transported away from the transfer device in the second transport direction (x). After a transport distance which is smaller than the workpiece width, the following workpiece can be advanced in the first transport direction (z).

The time required for the advance workpiece to be completely removed from the support by the transfer device can thus be used to further advance the hose and to produce the following length of hose by severing it from the hose. So it does not have to wait until the forward running workpiece has completely released the support surface. In this way, the subsequent workpiece can be transported immediately in the second transport direction (x) of the transfer device when the forward running workpiece has been carried away. The distance between the two workpieces can therefore be kept very small if necessary. In the same time interval, a larger number of workpieces can be removed from the transfer device compared to the method according to the prior art. After removal, the workpieces, so the pieces of hose, to bags processed, so that each time interval, a larger number of bags can be completed.

Preferably, the workpiece ahead should still fully cover the interfering edges when the subsequent workpiece passes over the interfering edges. But it is not harmful if the workpiece already partially releases the interference edges.

The feed of the subsequent workpiece can start immediately, as soon as the transfer device has taken the advance running workpiece. If the leading workpiece releases the interfering edges completely, the following workpiece should already be advanced so far that it has already covered the interfering edges with its leading end.

It is preferably provided that the workpiece in advance is transported further by a distance (Δx) which is smaller than the workpiece width reduced by the distance of the ends of the interfering edge facing the workpieces from the leading side edge of the workpiece during its transport in the second transport direction.

Thus, the advance of the following workpiece has advanced so far that this workpiece has already been pushed past the interference edges, when the workpiece in front just barely covers the interfering edges. Overall, the subsequent workpiece during its transport in the direction z that is held without contact above the transport surface and / or promoted.

Furthermore, it is advantageous if parts of the preceding workpiece and / or at least part of the following workpiece is displaced by means for displacement relative to the plane in which the workpiece lies, the direction of displacement comprising a component which is orthogonal to this level runs. In this case, therefore, preferably the side edge, which runs ahead in the transport in the second transport direction, slightly raised. The hose piece can thus contactlessly over the interference edges be guided. This is particularly desirable when there is no advance workpiece that could cover the clutter edges. The absence of a workpiece occurs, for example, when a workpiece is ejected from the production process due to an error or when production is started.

Further advantages of the invention, when the advance running workpiece or areas thereof is changed only by parts of the support surface in its altitude relative to the transfer device. It does not need the workpiece to be raised in whole, but only the lateral areas of the workpiece, which would otherwise come into contact with the transport table.

The present invention also relates to a device for changing the transport direction of successive workpieces.

A device according to the invention achieves the abovementioned object by means for changing the spatial position of a flat workpiece with which the following flat workpiece can be advanced by a specific distance (Δz), while the workpiece ahead is moved by the transfer device by a distance (Δx), which is smaller than the workpiece width, in the second transport direction (x) is further transportable.

Part of such a device may for example be a feed device, which then already advances the hose or the already isolated piece of hose, while the leading piece of tubing still covers said transport plane, in particular Störkanten. The movements of the two flat workpieces are coordinated, for example, by means of a geared connection between the feed device and the transfer device and / or by means of a control or regulating device. Preferably, the vote is made so that the transported in its longitudinal direction hose piece, at least almost, has reached its takeover position, while parts of the advance hose section still covers areas of the transport plane. In a preferred embodiment of the device, it is provided that the means for changing the spatial position include means for displacing the end of the flat workpiece and / or the leading end of the following workpiece relative to the plane in which said ends are initially located, wherein the direction of the displacement comprises a component which is orthogonal to the plane.

The idea of this inventive development is thus, for example, the end of the flat workpiece, in the present case, the trailing end of a piece of tubing, out of the plane in which this end and the leading end of the subsequent workpiece are initially to bring out. However, it is also possible to bring the leading end of the following workpiece out of this plane. The subsequent workpiece may be the tube, from which only later, after one of said ends was brought out of said plane, is singulated into a piece of tubing.

When changing the plane, it is important that the displacement be such that a motion component is orthogonal to the plane on which the ends initially rest.

By changing the plane of one of the ends of the feed of the subsequent workpiece can now be carried out without the leading end of which meets the end of the first workpiece and possibly compressed, unintentionally changed in position or even damaged.

The plane from which one of the two said ends is displaceable out, may be defined by a support plane on which the two ends are placed or rest. This support plane may be a component of a cutting device with which a piece of tubing is separated from the advanced tube, which, as already described, can be the subsequent flat workpiece. After this separation process, the severed tube section represents the flat workpiece, while the remaining tube then represents the subsequent flat workpiece. It it is clear that the cut produces the end of the flat workpiece and the leading end of the subsequent flat workpiece. The support plane can therefore be the counter-position of the cutting blade. Advantageously, the support plane comprises a groove which extends transversely to the longitudinal axis of the workpieces. In this groove, the cutting blade can be performed during the cutting process.

The device according to the invention thus ensures that the leading end of the tube or the already isolated piece of tubing is guided on or above the leading piece of tubing and can not touch the transport plane. In order to enable such a so-called "overlapping discharging", various technical elements are advantageously provided, which are explained in more detail below and in the physical description.

In a preferred embodiment of the invention, a pusher element is provided, with which the end of the flat workpiece, so for example, the end of the hose piece, in a region below the plane on which the end initially rests, can be pressed. This area can be a free space at the side or below the support level. For this purpose, the support plane, viewed in cross-section, hook-shaped profile, so that below the said support plane, a free space is arranged. The pusher element can then be arranged so that it can reach into this free space. The pusher element may comprise a pneumatic piston cylinder, with which a pusher finger or a pusher bar is movable. The pusher finger or the pusher bar then come into contact with it in an area of the hose piece, this area not resting on the level. If the pusher element is moved, the end of the hose piece thus flips off and slides along a side surface of the support element comprising the support plane until the end reaches the free space and aligns itself again due to restoring forces. Preferably, however, said free space, wherein the pusher element is advantageously arranged so that the restoring forces are still supported and the hose piece as straight as possible aligns. This avoids errors in the formation of a bottom at this end of the hose piece.

In a particularly advantageous embodiment, it is provided that the said device comprises at least regions of the support surface, which regions are displaceable or adjustable relative to the transfer device and / or to its transport surface. Thus, it is thus possible to adjust the position of the areas of the support surface so relative to the transfer device that the hose piece that is just discharged in its longitudinal direction on the support surface, does not touch the transport surface. For this purpose, appropriate adjustment, especially drives, provided.

When starting a machine, such as a bag making machine, which comprises the device according to the invention, the first piece of tubing naturally has no leading piece of tubing, which could cover the interference edges. Accordingly, it is provided that the first piece of tubing is guided on a displaced or displaced support surface, while it is sufficient for the subsequent tubing pieces or for the subsequent tube that they are discharged on the advancing piece of tubing, while the support surface remains in a rest position. However, a so-called "first piece of tubing" can also occur during production if a piece of tubing is removed from the transport path immediately after its separation, which can take place if there is a defect in the piece of tubing, for example a material defect. Such a piece of tubing no longer needs to be further processed into a bag if it subsequently has to be treated as broke due to the defect.

In one embodiment of said further embodiment of the invention, the support surface can be moved to a position in which it is located above the transport plane, so that the transport plane is shielded for the hose piece to be pushed forward.

In an advantageous embodiment of the invention it is provided that at least areas of the support surface are designed height adjustable. By support surface is meant that surface on which the bags rest during their transport path in their longitudinal direction. A height-adjustable support surface can thus be moved, for example, orthogonal to the transport plane of the transfer device. However, the movement can also be of any kind, the movement direction comprising an orthogonal component. With this embodiment, it is possible to raise the length of hose so far that it or at least its areas, which, if support surface and transport plane lie in one plane, would rest on the transport plane, does not touch the transport plane. In this case, the areas of the support surface are to be sufficiently raised so that the hose piece does not touch the transport plane even with its depending side regions.

It is particularly advantageous if the height-adjustable areas of the support surface facing the transfer device. Here are the height-adjustable areas of the support surface on the transverse transport plane on which the transfer device then takes over the bag. In this embodiment, therefore, the support surface is divided into two, wherein the transport plane of the transfer device facing part is adjustable in height or displaceable or movable.

It is also advantageous if the height-adjustable regions of the support surface are pivotable about a rotation axis which runs parallel to the first transport direction. The height-adjustable support surface is folded up, so to speak, from the transport plane and encloses an angle with this plane. This is advantageous because the piece of tubing is thereby bent up along a line parallel to its direction of extension and accordingly the parts which protrude laterally beyond the folded-up region of the support surface do not extend very far down but are rather kept horizontal. Therefore, the adjustment angle does not need to be particularly large. The height offset between the height-adjustable support surface and the transport plane can be 10 mm, if the hose piece with about one quarter to one third of its surface laterally beyond the support surface protrudes. The adjustment angle is advantageously between 0 ° and 45 °, but preferably between 10 ° and 20 °.

In a preferred embodiment of the invention, the device for changing the transport direction of the sacks for adjusting the height-adjustable regions comprises a suitable drive device. This drive device may be a reciprocating cylinder, preferably a piston-cylinder unit operable with compressed air. But any other drive device that can reliably space the height-adjustable support surface of the transport plane, is conceivable. A piston-cylinder unit which can be operated with compressed air has the advantage of rapid adjustability.

Further embodiments of the invention will become apparent from the description and the claims.

Fig. 1

Eine schematische Darstellung einzelner Schritte zur Verarbeitung eines Gewebeschlauches zu Säcken,

Fig. 2

Eine Draufsicht einer erfindungsgemäßen Einrichtung zur Änderung der Transportrichtung von flachen Werkstücken,

Fig. 3

Eine Seitenansicht einer erfindungsgemäßen Einrichtung zur Änderung der Transportrichtung von flachen Werkstücken gemäß Schnitt III-III in der Figur 2,

Fig. 4

Eine Draufsicht einer erfindungsgemäßen Einrichtung zur Änderung der Transportrichtung von flachen Werkstücken,

Fig. 5

Wie Fig. 4, jedoch mit weiter transportierten voraus laufenden und nachfolgenden Werkstücken,

Fig. 6

Prinzipskizze zur Umlenkung von flachen Werkstücken,

Fig. 7

Seitenansicht einer Vereinzelungseinrichtung,

Fig. 8

Seitenansicht einer Vereinzelungseinrichtung,

Fig. 9

Seitenansicht einer Vereinzelungseinrichtung,

The individual figures show:

Fig. 1

A schematic representation of individual steps for processing a fabric tube into sacks,

Fig. 2

A top view of a device according to the invention for changing the transport direction of flat workpieces,

Fig. 3

A side view of a device according to the invention for changing the transport direction of flat workpieces according to section III-III in the FIG. 2 .

Fig. 4

A top view of a device according to the invention for changing the transport direction of flat workpieces,

Fig. 5

As Fig. 4 , but with further transported ahead and following workpieces,

Fig. 6

Schematic diagram for the deflection of flat workpieces,

Fig. 7

Side view of a separating device,

Fig. 8

Side view of a separating device,

Fig. 9

Side view of a separating device,

The Fig. 1 schematically shows individual steps for processing a fabric tube to bags, as done in bag making device 1.

First, the fabric tube 2 is fed to the sack manufacturing device 1. This is advantageously done by unwinding a fabric tube forming a roll 3 in a unwinding device 4. Subsequently, the tube 2 experiences the so-called opening in the opening station 5. The fabric tube is guided around an inner tool which separates the two layers, so that the layers, if they were glued together in one of the manufacturing steps of the tube, separate. Only with separate layers can it be ensured that the following production steps can be carried out properly. Afterwards, the separate material layers of the hose are put back on top of each other.

The fabric tube 2 is now fed to the cross-cutting device 6, which separates the fabric tube into individual flat workpieces or hose pieces 22.

Subsequently, a change of the original transport direction z, in which the tube or the flat workpieces were transported in the direction of their longitudinal axes, takes place in the new transport direction x, so that the tube pieces 22 are no longer transported in the direction z of their tube longitudinal axis, but transversely thereto so that the ends of the flat workpieces are laterally accessible for the purpose of molding the floors.

In the following station, the bottom opening station 8, both ends of each flat workpiece are opened and the so-called bottom squares are laid. In the following valve station 9, a valve is placed and secured on one of the two open ends. The open floors are now closed in the bottom closing station 10, wherein two tabs are placed on each other and permanently connected to each other, for example by welding. The conclusion of the actual Sack manufacturing process forms the application of a bottom cover sheet on the floors in the cover sheet station 11. For this purpose, the cover sheets can also be welded. The finished bags are then placed on the bag stack 12 and transported away from there on unspecified manner.

The FIG. 2 shows a plan view of an advantageous embodiment of a device 7 according to the invention for changing the transport direction of flat workpieces. In this figure, the hose 2 can be seen, which by means of a feed device 19, which consists of a driven pair of rollers, through the nip of the hose 2 is guided, advanced through the cross cutter 6 in the direction z (direction of the longitudinal axis of the hose) becomes. Once the tube 2 has been advanced with the desired length by the cross cutter 6, the feed stops, and the cross cutter 6, which is not shown here, separates a piece of tubing 22 from the hose 2. The piece of tubing 22 has a width B in the second transport direction x. Subsequently, the separated piece of tubing 22 is taken from the transfer device 24, which is either already the actual transport device for transferring the tube pieces 22 in the individual stations to form sacks or the pieces of hose to the actual Transport device transfers. Two successive pieces of hose 22 are transported in the direction x spaced from each other. This spacing is achieved in that the transfer device, which may comprise at least two transport belts 25, only detect the hose pieces 22 with contact elements 26 which are arranged at regular intervals on the transport belt. However, it is sufficient to detect the tube pieces 22 in the region of the side edges 18, which represent the leading edges during transport in the direction x.

From the FIG. 2 It can be seen that for the gripping and removal of the tube pieces 22 by the transfer device these 22 must rest on the transport table 20 of the transfer device, which represents the transport plane, to a proper transport to guarantee. Therefore, the tube 2 projects laterally (in the direction x) beyond the support surface 13 during the feed in the direction z.

This transport table 20 is, as can be seen, divided into two, wherein the two parts are displaceable relative to each other in the direction z. In this way, the transport table can be adapted to different hose section lengths. However, this has the consequence that the tube 2 would collide with its front edge 14 during the feed against the inner edge of the right table part. The transport table 20 may, however, by design also include further cuts 27 which may form interference edges.

In order to avoid the collisions described, the support surface 13 is divided into a fixed part and a height-adjustable part 15. The height-adjustable part 15 is designed plate-like and articulated via a rotation axis 28 on the fixed part. The axis of rotation 28 extends in the feed direction z of the tube 2. Using a reciprocating cylinder 21 (see FIG. 3 ), the height-adjustable region 15 can now be pivoted about the axis of rotation 28, so that the part of the hose piece 22 which projects beyond the height-adjustable region 15 in the x-direction, in particular its side edge 18, does not touch the transport table 20. The angle α, which occupies the height-adjustable region 15 to the plane of the support surface 13, is chosen to be sufficiently large.

In other embodiments, a plurality of height-adjustable regions 15 can also be provided. These 15 can also be arranged, for example, articulated or nested. In a further embodiment, the entire support area 13 can be raised.

The reciprocating cylinder 21 is articulated with its piston rod 30 via a hinge 29 on the height-adjustable area. The housing of the reciprocating cylinder 21 is movably connected to the machine frame in a suitable manner, which, however, in the FIG. 3 not shown.

The Figures 2 and 3 show an embodiment of the invention in which each piece of tubing individually, ie discharged without touching contact with the leading piece of tubing, so brought to the support surface and then separated. At least in the period beginning at the time when the leading edge 14 has almost reached the left incision 27 and ending at the time when the leading edge 14 has passed over the right incision 27, the height adjustable portion 15 is in his in the FIG. 3 shown, superscript position. In the remaining periods, this area is in its lowered position, in which the support surface, the height-adjustable part 15 and the transport table form a plane, preferably a horizontal plane.

In the FIGS. 4 and 5 is a further embodiment of the invention, which also with the embodiment according to the Figures 2 and 3 can be combined. In the FIG. 2 a discharged tube section 22 is shown, which rests on the support 13 and the height-adjustable region 15. Just before this piece of hose 22 is taken by the contact elements 26, the height-adjustable portion 15 must be lowered. After the contact elements 26 have grasped the tube piece 22 and have already pulled it forward in the direction x for a short distance, the tube 2 can already be advanced again by means of the feed device 19. In the FIG. 4 this is shown. It can be seen that, with further preference of the tube piece 22, this part of the transport table 20 covers, so that the tube 2 can be advanced without interference and damage. In FIG. 5 is shown that the tube 2 has already been advanced by a distance z ₁ , while the leading piece of tubing was pulled forward x only a distance x ₁ in the second transport direction, which is smaller than the width (B) of the tube piece 22 and Hose 2. How the FIG. 5 it can be seen further, the feed means ensure that the hose with its leading end has already swept over the Störkanten, while the trailing side edge of the leading hose has not yet swept the Störkanten. In this way, the interference edges during the advancement of the tube 2 are completely from the screened in advance hose section, so that the hose can be discharged without interference.

In the other figures, which are explained below, further technical elements are listed, which are advantageous in the context of the described embodiment of the invention. This concerns, for example, the pusher finger 127.

The FIG. 6 shows again changing the transport direction of workpieces 2, which are initially transported in the direction z. To get over the interference edges 27 away, the workpiece 2 is to be advanced by the distance .DELTA.z. However, in order that the workpiece 2 does not come into contact with the interference edges, the workpiece 22 running ahead is in this period of time, which is required to advance the workpiece 2 by this distance .DELTA.z, preferably a maximum of the distance .DELTA.x to transport. However, it is also possible to further transport the workpiece 2 in the direction x by the distance Δx + x ₁ , if this distance is smaller than the bag or workpiece width B. In this case, although the Störkanten 27 are released in part. The left interference edge 27 (in the FIG. 6 this is the interfering edge closest to the workpiece 2) is usually still completely covered by the workpiece 22 when the leading end of the workpiece 2 has passed them. When the workpiece 2 reaches the second interfering edge 27, it may not be completely covered by the workpiece 22. However, since the workpiece 2 still partly rests on the workpiece 22, the probability that the first collides with the interfering edge is extremely low.

The FIG. 7 shows a side view of the separating device 113. The fabric tube 2 is advanced by the feed rollers 114 until a certain hose length or a desired sack format length is reached behind the cross-cutting device 6. Thereafter, the feed of the fabric tube is stopped for a short time. In the cross-cutting device 6, a piece of tubing 22 (see Fig. 8 ) separated from the fabric tube 2. The cross-cutting device 6 comprises for this purpose a knife 115 which is fastened on a knife holder 117. The knife is via a knife drive 116 in z-direction movable. Beforehand, the fabric tube 2 is fixed by clamp plates 121, 122 by moving them 121, 122 in -y direction. The level 143 serves as an abutment during the cutting process. The end of the tube piece 22 as well as the leading end of the tube 2 are on this level.

In FIG. 9 It can be seen that after the cross-section of the fabric tube 2, the tube piece 22 is pressed by a Schlauchabschnittfixierer 123 on a table 20, which represents the subsequent transport plane 20 of the tube pieces 22. At this moment, the height-adjustable portion 15 should be in its lowered position. To fix the tube piece 22, a fixing plate 126 is moved by two cylinder pistons 124, 125 in the direction of the tube piece 22. This ensures that the tube piece 22 can not slip in its position. It should be noted that the fixing plate 126 already fixes the tube piece 22, while this 22 is still held by the clamping plates 121, 122 and / or is still in contact with a pressing finger 127 of a pressing member 119. The piece of tubing never remains unfixed throughout the singulation process until it is transferred to the transverse transport device.

If the tube piece 22 is fixed by means of the tube portion fixer 123 and the clamping plates 121, 122 have been removed again, it is pressed by the pusher element 119 into a notch 120 (FIG. FIG. 9 ). In this case, the end of the hose piece is changed in its vertical position and leaves the plane 143. For this purpose, the pusher member 119 is equipped with a pusher finger 127 which can be moved via a cylinder piston 128 in the direction of the hose piece end. The notch 120 is preferably formed in that the support surface or the counter-position for the knife 115 is formed by a profile rail 143 which vertically below the support surface for the knife a clearance, just the notch 120 includes. Only in this way can it be ensured that the end of the tube piece 22, which has been pressed down by the pusher finger 127, is exposed again. Now, the hose piece after lifting the Fastening plates 126 of the Schlauchabschnittfixierers 123 detected in the manner already described and transported in the direction x.

The listed elements and the described process steps are necessary to now, while the abzutransportierende piece of tubing still partially rests on the support surface 15, the hose 2 can continue to advance, so that the front end 14 of the hose in part with the advance hose section 22nd overlaps, as it is in the FIGS. 4 and 5 is shown. LIST OF REFERENCE NUMBERS 1 Bag-making apparatus 2 Fabric hose / tubular material 3 reel 4 handling facility 5 Location separating station 6 Cross-cutting device / separating device 7 Device for changing the transport direction 8th Bottom opening station 9 valve station 10 Floor closing station, Zulegestation 11 Cover Station 12 bag stack 13 Support surface for the flat workpiece 14 Leading edge of the tube piece 22 15 Height-adjustable region of the support surface 13 16 Edge of the support surface 17 17 Front edge of the height-adjustable area 18 Side edge of the flat workpieces 2 19 feeder 20 Transport tables of the transfer device 21 Hubkolbenzylinder 22 Piece of hose / tube section 23 24 transfer device 25 conveyor belts 26 contact element 27 incision 28 axis of rotation 29 joint 30 reciprocating 113 separating device 114 feed rollers 115 knife 116 knife drive 117 knife holder 118 119 pusher element 120 notch 121 Catches sheet 122 Catches sheet 123 Schlauchabschnittfixierer 124 cylinder piston 125 cylinder piston 126 Fixing plate 127 pusher finger 128 cylinder piston 129 takeaway 130 131 132 133 134 135 136 137 138 139 140 141 142 level 143 rail 144 feather 145 B Width of the hose 2 and the hose piece 4 α Angle between the plane of the support surface 15 and the plane of the height-adjustable region 15th x second (new) transport direction of the tube piece 22nd x1 transport distance z first transport direction of the hose 2 and the hose piece 22nd z1 transport distance

Claims (15)

1. Method of transporting flat workpieces (2, 22) having a workpiece width (B), in particular flexible-tube portions (2, 22),

   - in the case of which an individual flat workpiece (2, 22) or a succession (2) of interconnected flat workpieces, from which a flat workpiece is to be separated, is advanced onto a bearing surface (13) in a first transporting direction (z) by means of an advancement device (19),

   - in the case of which in each case the individual or the separated flat workpiece (2, 22) is conveyed away from the bearing surface (13), by means of a receiving device (20, 24-27), in a second transporting direction (x), which is located parallel to the plane of the flat workpiece (2, 22) and runs orthogonally in relation to the first transporting direction (z), wherein, immediately prior to and/or during transportation in this transporting direction (x), the flat workpiece (2, 22) has at least its side regions resting on a transporting plane (20) of the receiving device (20, 24-27),

   wherein
   a following flat workpiece (2, 22) or the succession of interconnected flat workpieces is advanced at least by a certain distance (Δz), while the preceding workpiece is transported onward in the second transporting direction (x) by a distance (Δx) which is smaller than the workpiece width (B), and
   the preceding workpiece and the following flat workpiece are transported at a distance apart from one another in the transporting direction (x),
   characterized
   in that the
   workpieces are gripped by contact elements (26) of a receiving device (24), wherein the contact elements (26) are arranged at regular intervals on at least two transporting belts (25), wherein the workpieces are gripped by the contact elements (26) merely in the region of the side edges (18) which constitute the leading edges during transportation in the transporting direction (x).
2. Method according to Claim 1,
   characterized in that
   the preceding workpiece is transported onward by a distance (Δx) which is smaller than the workpiece width (B) reduced by the distance (x₁) between that end of the protruding edge which is directed towards the workpieces and the leading side edge (18) of the workpiece as the latter is transported in the second transporting direction (x).
3. Method according to one of the preceding claims,
   characterized in that
   at least parts of the preceding workpiece and/or at least parts of the following flat workpiece are displaced by means (120, 143, 121, 122, 119, 127, 128) for displacement relative to the plane in which the workpiece is located, wherein the direction of displacement comprises a component which runs orthogonally in relation to the plane.
4. Method according to one of the preceding claims,
   characterized in that
   the preceding workpiece or regions (18) thereof is or are altered in height position relative to the receiving device (20) by parts (15) of the bearing surface (13).
5. Apparatus for transporting flat workpieces (2, 22), in particular flexible-tube portions (2, 22), having a workpiece width (B),

   - in the case of which an individual flat workpiece (2, 22) or succession of interconnected flat workpieces, from which a flat workpiece is to be separated, can be conveyed onto a bearing surface (13) in a first transporting direction (z) by means of an advancement device (19), wherein the end of one flat workpiece and the leading end of the following flat workpiece or of the succession are located, in the first instance, on a common bearing surface within a plane (142),

   - in the case of which the individual or the separated flat workpiece (2, 22) can be conveyed away from the bearing surface (13), by means of a receiving device (20, 24-27), in a second transporting direction (x), which is located parallel to the plane of the flat workpiece (2, 22) and runs orthogonally in relation to the first transporting direction (z), wherein, immediately prior to and/or during transportation in this transporting direction (x), the flat workpiece (2, 22) has at least its side regions resting on a transporting plane (20) of the receiving device (20, 24-27),

   having
   means
   (120, 143, 121, 122, 119, 127, 128) which are intended for altering the spatial position of a flat workpiece (2, 22) and by way of which the following individual flat workpiece (2) or the succession of interconnected flat workpieces can be advanced by a certain distance (δz), while the preceding workpiece (22) has been transported onward in the second transporting direction (x), by the receiving device (20), by a distance (δx) which is smaller than the workpiece width (B),
   wherein the preceding workpiece and the following flat workpiece can be transported at a distance apart from one another in the transporting direction (x),
   characterized
   in that the
   workpieces can be gripped by contact elements (26) of the receiving device (24), wherein the contact elements (26) are arranged at regular intervals on at least two transporting belts (25), wherein the workpieces can be gripped by the contact elements (26) merely in the region of the side edges (18) which constitute the leading edges during transportation in the transporting direction (x).
6. Apparatus according to the preceding claim,
   characterized in that
   the preceding workpiece can be transported onward by a distance (δx) which is smaller than the workpiece width (B) reduced by the distance (x₁) between that end of the protruding edge which is directed towards the workpieces and the leading side edge (18) of the workpiece as the latter is transported in the second transporting direction (x).
7. Apparatus according to either of the two preceding claims,
   characterized in that
   the means (120, 143, 121, 122, 119, 127, 128) for altering the spatial position comprise a device (120, 143, 121, 122, 119, 127, 128) for displacing the end of the flat workpiece (22) and/or the leading end of the following workpiece (2) relative to the plane (142) in which the aforementioned ends are located in the first instance, wherein the direction of displacement comprises a component which runs orthogonally in relation to the plane.
8. Apparatus according to one of the three preceding claims,
   characterized in that
   the means (120, 143, 121, 122, 119, 127, 128) for displacing the end of the flat workpiece comprise a pusher element by way of which the end of the flat workpiece can be pushed into a region (120) beneath the plane (142).
9. Apparatus according to one of the four preceding claims,
   characterized by
   the provision, in addition, of a device (13, 15, 21, 28, 29, 30) by way of which the flat workpiece (2, 22), during transportation thereof in the first transporting direction (z), can be retained and/or conveyed in contactless fashion above the transporting plane (20).
10. Apparatus according to one of the five preceding claims,
    characterized in that
    the device comprises at least regions (15) of the bearing surface (13) which can be displaced or adjusted relative to the receiving device (20).
11. Apparatus according to one of the six preceding claims,
    characterized in that
    the device comprises at least regions (15) of the bearing surface (13) which can be adjusted in height relative to the receiving device (20).
12. Apparatus according to Claim 10 or 11,
    characterized in that
    the displaceable or adjustable regions (15) of the bearing surface (13) are directed towards the receiving device.
13. Apparatus according to Claim 11,
    characterized in that
    the height-adjustable regions (15) of the bearing surface (13) can be pivoted about an axis of rotation (28) which runs parallel to the first transporting direction (z).
14. Apparatus according to Claim 11,
    characterized in that
    a drive device (21) is provided for adjusting the height-adjustable regions (15).
15. Apparatus according to the preceding claim,
    characterized in that
    the drive device (21) is a piston/cylinder unit (21) which can be operated by compressed air.

Images