EP2116470B1 - Method for applying flat straps around packages and device for carrying out the method - Google Patents

Abstract

The method involves carrying a belt starting end of a strap belt to a grip unit (7) based on a locking head (4) of a strapping device (1), where the head is positioned at a package (5). The belt starting end is clamped and guided around the package by the grip unit. The belt starting end is supplied to the head and is retained on the head. The strap belt is tightened up to a preset position by withdrawing into the head. The belt starting end is connected with the withdrawn strap belt, where the strap belt is separated from a supply role. An independent claim is also included for a strapping device for applying of a flat strap belt from a plastic or metal material around packages.

Description

The invention relates to a method for applying flat Umreifungsbändem of a plastic or metal material to packages by means of a strapping device. In addition, the invention is directed to a strapping device for applying flat Umreifungsbändem of a plastic or metal material to packages.

Strapping devices for strapping objects, in particular packages count in different versions of the prior art. The basic principle of strapping is to position a strapping head on a package to be strapped, guide a strapping band around the package, tension the strapping band, and connect its ends within the closure head. The overlapping ends of the prestressed strapping band are connected to one another in a material-locking or form-fitting manner. The removed from a supply roll strapping is separated and the closure head lifted from the package. These steps are automated.

Strapping is subject to extreme loads, in particular dynamic loads which occur during the transport of the packages can become so great that the strapping tapes break. For example, rod or tube-like metal products are bundled by strapping. When such bundles are transported by means of a crane, deflection forces occur forcibly outside the points of application of the stop means, which in turn leads to displacement of the bars or tubes with one another. The strapping must be the resulting Pick up loads. Theoretically, it is possible to provide a larger number of strapping bands to prevent such displacements. However, tube bundles and other rod-like products are so-called rigid packages which have a very limited flexibility. Since the strapping bands must be strongly biased in order to avoid shifts within the bundle, additional shock loads, such as lifting or lowering the bundle by means of a crane under flexure of the bundle, can lead to stress peaks within the strapping bands that exceed the limit of strapping straps lie. Similarly large loads occur when shipping the bundles.

As part of the DE 93 19 856 U1 An apparatus for necking packages or the like will be described. For this purpose, inter alia, a clamping device for a thread beginning as well as a knotting device for forming a knot by knotting the thread start is provided with the tracking thread. There are also means for moving the thread around the package to be tied. The means for guiding the thread have a rotatably mounted circular ring, on which the thread clamping head is attached. As a result, the thread can be guided several times around the package to be strapped.

Quite apart from that describes the EP 0 388 761 A a strapping machine for packing packages of any type and size. Among other things, this is based on a vertically or horizontally movable packing belt channel. In addition, another packaging tape channel piece is provided. The two belt strapping systems for longitudinal strapping and strapping are arranged so that the strapping belt is conveyed to a specific central operator location becomes. In this way, both longitudinal and transverse strapping can be performed by the operator from a single location.

Proceeding from this, the present invention seeks to provide a method and apparatus for bypassing or flattening flat Umreifungsbändem of a plastic or metal material, in particular steel, to show packages that very high because of their high weight, their volume or their critical shape Make demands on the transport protection created by strapping.

This object is achieved by the method according to claim 1 and the associated apparatus for performing the method according to claim 8.

In the context of the invention according to claim 1, a method is proposed in which the beginning of the tape is pushed through tape guide channels, so that the strapping tape is guided over the entire length.

The technical problem to be solved in this context is the design of the tape guide channels, which inevitably have to have a crossing point on a side opposite the closure head side. In the method according to claim 1, a first band guide channel is provided which surrounds the package and a second band guide channel, which connects to the first channel and also surrounds the package. Theoretically, further tape guide channels can be provided to make not only double but triple or quad strapping. The technical complexity of triple or quad strapping but is very high, as in the crossing point of the respective band guide channels Possibilities must arise in order to open the respective inner band guide channels when the closure head tensions the strapping band.

The core of the method according to claim 1, therefore, is that the closure head opposite intersection of the band guide channels is released. In a first embodiment, the inner, closer to the package strip guide channel is executed divided, wherein at least one of its sections is moved out of the crossing point. When the crossing point is released, the strapping band can be pulled into the closure head and thus tensioned.

At the tape guide channels spring-loaded holding means are provided for the strapping, which open automatically overcoming the spring force and release the strapping, so that it can get to the package to the plant.

Theoretically, it is possible to make both tape guide channels so that they are opened at the intersection, for example, if rod-shaped packages are to be introduced in a sense not in the axial direction of the openings formed by the tape guide channels, but in the radial direction, so to speak, transversely to the tape guide channels in the strapping. For the function of Doppelumreifung, however, it is only necessary to form only the inner band guide channel so that the intersection point is releasable.

While in the embodiment described above, it is assumed that an inner and at least one further, outer band guide channel is provided, the alternative according to claim 3 is to rigidly form the band guide channels and in Connecting intersection point. For this purpose, an intersection is provided. In the crossing part, there is also an inner and an outer band channel which is connected to the first and second band guide channel, respectively. The essence is, however, that not the entire band channel must be moved out of the crossing point, but that only one of the inner band channel of the outer band channel separating slide must be opened to both the inner strapping and the outer strapping of the respective Pull out the ribbon channels and the ribbon guide channels. Such a slider has the advantage that it is a much smaller moving component, as in a whole band guide channel. Therefore, only smaller drive units are required. The construction is more compact. This is due to the fact that the slider has two functions during the running in of the band: on the one hand, it is the wall of the outer band channel but at the same time also the boundary of the inner band channel. Preferably, the slider is even configured in a U-shape such that it forms three walls of the inner band channel within the crossing region like a fork. By retracting the slider, both the inner and the outer band channel are released at the same time.

Another essential element in this type of tape guide is that the strapping enters after entering the first band guide channel in the second band guide channel, via a bypass channel which extends along the closure head. The bypass channel is connected to the end of the first tape guide channel and the beginning of the second tape guide channel. This bypass channel is preferably positioned as close as possible to the tape inlet and outlet channel of the closure head, so that the distance of the belt loops is minimized. In this way it is ensured that the strapping is not due to lateral displacement of a or both of the belt loops loosens, with the result that the bias of the strapping decreases.

It is considered in this context to be particularly advantageous if the bypass channel is opened after the application of the belt loops and the belt loop is displaced from the bypass channel in the direction of the tape inlet and outlet channel of the closure head. These measures can be done with a reduced band loop before tightening the strapping. Regardless of this, it is considered expedient if the displaced belt loop is prevented from displacing out of this position into the bypass channel after being displaced into the region of the belt inlet and outlet channel by at least one blocking element. The blocking element is preferably a pawl which is mechanically coupled to a pusher element which is used to displace the second band loop into the band inlet and outlet channel.

After both strap loops of the pre-strapped strap are securely positioned, after tightening the strapping band in a known manner, the joining of the strap ends, within the closure head. This can take place cohesively, positively by direct compression or by using closure sleeves.

In the strapping device according to claim 8, the tape end is not guided by a gripping unit, but by tape guide channels, which surround the package to be strapped twice. The arrangement and operation of the Umreifungsband leading channels has been explained above.

The inner band guide channel adjacent to the package is divided in a first embodiment so that at least one of its sections can be moved out of the crossing region, in particular swung out. When moving out or swinging out of the sections, the packaging tape is freed from surrounding parts and can be pulled out of the tape guide channel until it rests against the package.

In the alternative embodiment according to claim 8 comes in an intersection of the outer part of the inner band channel separating slider used, which is preferably configured U-shaped and forms a portion of the inner band channel. The slider covers by the U-shaped geometry of the upper band channel from above.

While this slide is only intended to release the strapping at the intersection so that it can come to rest during clamping on the package, the thrust element according to claim 16, the strapping from the bypass channel in the Bandein- and outlet channel shift. A sliding back of the displaced belt loop is prevented by a blocking element which holds the strapping band in the band inlet and outlet channel even when the pusher member is retracted.

Fig. 1 und 2

eine erste Ausführungsform einer Umreifungsvorrichtung in zwei Seitenansichten, die nicht der Erfindung entspricht und lediglich die grundsätzliche Funktionsweise erläutert;

Fig. 3

die Umreifungsvorrichtung der Fig. 1 und 2 mit verschwenktem Verschlusskopf;

Fig. 4

die Umreifungsvorrichtung der Fig. 1 und 2 mit einer um die Längsachse des Führungsrings verschwenkten Greifeinheit;

Fig.5

die Position des Verschlusskopfes der Umreifungsvor- richtung nach den Fig. 1 und 2, wenn die Greifeinheit am Verschlusskopf vorbei geführt und wieder in die Anfangs- position verfahren wird;

Fig. 6

die erfindungsgemäße zweite Ausführungsform einer Umreifungsvorrichtung mit geteiltem Bandführungskanal;

Fig. 7

die Umreifungsvorrichtung der Fig. 6 in der Draufsicht;

Fig. 8

eine perspektivische Darstellung einer Doppelumreifung;

Fig. 9

in perspektivischer Darstellung ein Kreuzungsteil, wie es bei einer mit Bandführungskanälen versehenen Umreifungsvor- richtung gemäß Fig. 10 zum Einsatz kommt;

Fig. 10

eine Seitenansicht einer Umreifungsvorrichtung mit fest- stehenden Bandführungskanälen und Kreuzungspunkt;

Fig. 11 bis 13

der schematische Ablauf der Verlagerung eines Um- reifungsbands aus einem Bypasskanal in Richtung des Bandein- und Auslaufkanals des Verschlusskopfes;

Fig. 14 und 15

eine Seitenansicht eines Verschlusskopfes mit ge- schlossenem und offenem Bypasskanal;

Fig. 16 und 17

vergrößerte Darstellungen der Fig. 14 und 15 und

Fig. 18 und 19

eine perspektivische Darstellung einer Greifeinheit, wie sie im Rahmen der ersten und nicht zur Erfindung gehörigen Ausführungsform zum Einsatz kommt.

The invention will be explained in more detail with reference to the embodiments illustrated in the schematic drawings; show it:

Fig. 1 and 2

a first embodiment of a strapping device in two side views, which does not correspond to the invention and only explains the basic operation;

Fig. 3

the strapping device of Fig. 1 and 2 with swiveled closure head;

Fig. 4

the strapping device of Fig. 1 and 2 with a gripping unit pivoted about the longitudinal axis of the guide ring;

Figure 5

the position of the closure head of the Umreifungsvor- direction after the Fig. 1 and 2 when the gripping unit is guided past the closure head and moved back to the initial position;

Fig. 6

the second embodiment of a strapping device according to the invention with a split band guide channel;

Fig. 7

the strapping device of Fig. 6 in the plan view;

Fig. 8

a perspective view of a Doppelumreifung;

Fig. 9

in a perspective view of an intersection, as in a provided with band guide channels Umreifungsvor- direction according to Fig. 10 is used;

Fig. 10

a side view of a strapper with fixed band guide channels and crossing point;

Fig. 11 to 13

the schematic sequence of the displacement of a strapping band from a bypass channel in the direction of the band inlet and outlet channel of the closure head;

FIGS. 14 and 15

a side view of a closure head with closed and open bypass channel;

FIGS. 16 and 17

enlarged views of the FIGS. 14 and 15 and

FIGS. 18 and 19

a perspective view of a gripping unit, as used in the context of the first and not part of the invention embodiment.

Fig. 1 shows a first side view of a first and not belonging to the invention embodiment of a strapping device 1. The strapping device 1 comprises a frame 2 with a movable in height boom 3, on which a closure head 4 is arranged. The closure head 4 serves a in Fig. 8 illustrated strapping 17 output, which is to be led around a package 5. In this embodiment, the package 5 is configured hexagonal in cross-section. For example, it is a bundle of rods or tubes. The smaller of the two hexagons shown should make it clear that the package 5 can have different sizes. In this embodiment, the closure head 4 is located above the package 5. It is positioned so that the closure attached by the closure head 4 is always located centrally on the top of the package 5. For this purpose, the closure head 4 can be displaced in not horizontally positioned packages 5 in a manner not shown in the horizontal direction.

The strapping device 1 further comprises a guide ring 6, which surrounds the package 5 and is rotatably mounted about its longitudinal axis L. With the guide ring 6, a gripping unit 7 is fixedly connected. If the Guide ring 6 is set in a rotational movement, the gripping unit 7 rotates about the longitudinal axis L and thus to the package. 5

The gripping unit 7 is intended to grab a issued by the closure head 4 strapping 17 at its beginning of the tape 31 and to fix it by clamping. For this purpose, the gripping unit 7 is provided with a jaw 8. In this embodiment, the jaw 8 would act on the wider flat sides of the strap 17. Alternatively, the clamping jaw 8 can also act on a narrow side of the strip beginning 31.

After the beginning of the tape 31 has been clamped in the gripping unit 7, 4 strapping tape 17 is output via the closure head and the guide ring 6 is driven, so that the gripping unit 7 moves with the beginning of the tape not shown in the direction of arrow P. Since the gripping unit 7 must be arranged to accommodate the beginning of the tape on a relative to the closure head 4, it is necessary to move the closure head 4 before the first complete rounding of the gripping unit 7 from the trajectory B drawn with a broken line, so that the gripping unit 7 does not the closure head 4 collided. For this purpose, in this embodiment, the frame 2 with the boom 3 and the closure head 4 is pivoted about a horizontal axis in the direction of the arrow P1 ( Fig. 3 ). Other versions with z. B. linear adjustment are possible.

The FIGS. 18 and 19 show a perspective view of a gripping unit 7 in two different positions. The gripping unit 7 comprises a supporting jaw 42 and a clamping jaw 43 which is displaceable in the direction of the arrow P8 in the direction of the supporting jaw 42. The support jaw 42 serves as an abutment for the jaw 43. Between the support jaw 42 and the jaw 43 is the band beginning 31 of the strapping band 17 is clamped, specifically over the narrow longitudinal edges of the strapping band 17. Thus, the strapping band 17 does not buckle in this type of fixation, the jaw 43 and the support jaw 42 are arcuately curved in their course. In addition, the jaw 43 and the jaw 42 are configured in a substantially L-shaped cross section so that the tape top and the tape bottom are guided inside the gripping unit 7.

In a manner not shown, the clamping jaw 43 is pressed under the influence of a spring force in the direction of the support jaw 42.

After the gripping unit 7 has almost completely completed a second or third or fourth rotation of the package, the closure head 4 is pivoted back and the gripping unit 7 in the in Fig. 4 stopped position shown. The gripping unit 7 is now located on the rear side of the closure head 4. In this position, the entrained beginning of the tape to be introduced into the closure head 4 again. For this purpose, the strapping device 1 uses a transport device 9 in the form of a transport roller, which transports the strip beginning after the clamping of the gripping unit 7 via an arcuate insertion ramp 10 in a Bandein- and outlet channel on the tape inlet side 11 of the closure head 4. For this purpose, it is necessary to open the jaw 43 completely or at least so far that the band has enough space for the above-described transport. Subsequently, the tape end is clamped by the closure head 4 in a known manner and excess strapping 17 is withdrawn through the tape outlet to tension the strapping 17 with a predetermined tensile force. In this case, the closure head 4 is located very close to the surface of the package 5. Finally, the tensioned strapping 17 is connected to the strip beginning 31 ( Fig. 8 ). When Umreifungsbändem 17 off Steel is done for example by welding. Of course, positive connections are possible by direct compression or using closure sleeves. The still connected to the supply roll end of the strap 17 is separated. The closure head 4 is lifted from the package 5 and the package 5 can be removed from the strapping device 1. Subsequently, the gripping unit 7 moves back to the starting position, as in Fig. 1 is shown. Either this, the closure head 4 can be pivoted again in the direction of the arrow P3, as it Fig. 5 shows, so that the closure head 4 is returned to the starting position with the same direction of rotation. Alternatively, it is of course also possible to move the gripping unit 7 against the original direction of rotation of the guide ring 6 back to the starting position.

The 6 and 7 show a second embodiment according to the invention of a strapping device 12, which operates on a different principle than that of Fig. 1 to 5 and 18, 19 ,

The strapping device 12 according to Fig. 6 does not require a gripping unit 7 in order to guide the beginning of the strip 31. It has for this purpose band guide channels 13, 14. In the present case, a double strapping is to be created. Therefore, two tape guide channels 13, 14 are provided. In a double strapping, as in Fig. 8 is shown, there is inevitably a crossing point K, in which the belt loops 15, 16 of the strapping 17 intersect. When using belt guide channels 13, 14, it is unavoidable during the application of the belt loops 15, 16 that one of the belt guide channels 13, 14 is closer to the package 5 than the other. If the strapping 17 is tensioned, it must be ensured that the running at the intersection K outside belt loop 15 is not with the inside lying band guide channel 13 collided. Therefore, in the embodiment of the Fig. 6 provided to pivot the inner band guide channel 13 to release the crossing point K. In Fig. 6 the inner band guide channel 13 is shown in two positions. Once in the closed position and once in the open position in which the lower ends of the inner band guide channel 13 are spaced from each other. After applying the double strapping the outwardly pivoted portions 18, 19 of the inner band guide channel 13 are brought together again, so that the next strapping process can be performed.

Fig. 7 illustrates once again, the intersecting course of the two band guide channels 13, 14 and their connection to the closure head. 4

As an alternative to the division of the inner band guide channel 13 is in the embodiment of a strapping device 20 according to Fig. 12 provided to use an intersection part 21, whose operation is described below with reference to Fig. 9 is explained. Basically, in this embodiment, none of the band guide channels must be pivoted. They are executed in a sense rigid and connected to each other via the intersection part 21. The crossing part 21 has two superimposed band channels, one of which, the inner, the package 5 closer band channel 22 and one of the package 5 further away outer band channel 23 is. As based on the Fig. 9 It can be seen, the outer band channel 23 has a greater depth than the inner band channel 22. The inner band channel 22 crosses the outer band channel 23 and is of this in the region of the crossing point K via a displaceable in the direction of arrow P4 slide 25 of the outer band channel 23 separately. The slider 25 is in the position shown in a closed position and covers by its U-shaped configuration with its lower leg 34, the inner band channel 22 and with its upper leg, the outer band channel 23 in the image plane from above. An insertion bevel 24 ensures that in the direction of the arrow P4 entering the crossing part 21 strapping 17 passes in the image plane below the slide 25. When applying the second belt loop 16, the strapping 17 passes from the direction of the arrow P5 in the inner band channel 22 and extends between the rear leg 34 and the upper leg 35 of the slider 25. After the strapping 17 has arrived in the closure head 4 and clamped there , the slider 25 is retracted in the direction of the arrow P3, so that the band channels 23, 24 are released. As a result, this can also emerge from the outer band channel 23 when tensioning the strapping band 17. After both belt loops 15, 16 have been pulled out of the crossing part 21, the slider 25 is again moved into the illustrated closure position, so that a further strapping process can take place.

In principle, the two belt loops 15, 16 should run as close together as possible. In other words, the distance A ( Fig. 8 ) as small as possible. This assumes that the tape guide channels 26, 27, as they are in Fig. 10 can be seen, as close together as possible. However, this would also mean that the crossing part 21 has to be made longer if the belt loops 15, 16 at the point of intersection K are at a very acute angle to each other. On the other hand, the belt loops 15, 16 in their in the Fig. 8 shown upper region, ie in the region of the closure head 4 due to the parallel guide in a relatively small distance from each other. This results in that the band guide channels 26, 27 are not only arcuately curved, but slightly wound in the direction of their longitudinal extent, that are twisted about their longitudinal axis. It is in the band guide channels 26, 27 therefore geometrically complicated components. Therefore, it is expedient for manufacturing reasons, the Band guide channels 15, 16 to build multi-part, wherein at least the area between the closure head 4 and the crossing part 21 is divided into two longitudinal sections, which are centrally connected to each other.

This results in the Fig. 10 recognizable bulbous shape of the band guide channels 26, 27 in this side view.

In order to reduce the distance A between the upper two regions of the two belt loops 15, 16, it is provided in a bypass channel 28 extending parallel to the closure head 4 region of the belt loops 15, 16 in the direction of the belt loop in the band inlet and outlet channel 29 of the closure head 4 to relocate.

This principle is explained below on the basis of Fig. 11 to 13 explained. In a highly schematic representation shows Fig. 11 in the upper half a Bandein- and outlet channel 29, which is located within the closure head 4, not shown. In this Bandein- and outlet channel 29 is located with reference to Fig. 8 a partial section of a first belt loop 15. Parallel to the belt inlet and outlet channel 29 extends the bypass channel 28, in which the second belt loop 16 is located. The band inlet and outlet channel 29 is spatially separated from the bypass channel 28, so that the in Fig. 8 shown end of tape 31 can easily pass through the bypass channel 28 when creating the belt loop 16. The bypass channel 16 is partially bounded on its narrow side facing away from the band inlet and outlet channel 29 by a pusher element 32. After both band loops 15, 16 have been laid and the band end 31 has been fixed in the closure head 4, the bypass channel 28 is opened. Subsequently, the belt loop 16 is displaced by a lateral movement of the thrust element 32 of the bypass channel 28 in the direction of the belt inlet and outlet channel 29 (arrow P6). As a result, the belt loops 15, 16 are close together. Before the pusher element 32 is withdrawn again (arrow P7), a blocking element 33 engages laterally behind the displaced belt loop 16, so that the belt loop 16 can not slip back into the bypass channel 28 again.

The lateral displacement of the belt loop 16 from the bypass channel 28 takes place before the strapping band 17 is tensioned.

The blocking element 33 is preferably a pawl which is coupled to the pusher element 32. The thrust element 32 shown in greatly simplified form is preferably configured fork-shaped and encompasses both the top and bottom of the belt loop 16 to be displaced in order to guide it exactly even during the displacement.

The FIGS. 14 and 15 show in side view a much simplified closure head 30, in particular, the area of the band guide channels is of interest. In Fig. 14 or in the enlarged view of Fig. 16 It can be seen that a partial section of the first belt loop 15 is located in a belt inlet and outlet channel 29, while the second belt loop 16 is located in the closed bypass channel 28. The bypass channel 28 is constructed in two parts and comprises a fixed upper part 36 and a pivotable lower part 37, which via a pivot mechanism 38 to a lying above the upper part 36 pivot point S in the in Fig. 15 or 17 shown position is displaced. The pivot point S is located at a relatively large distance from the bypass channel 28, so that the lower part 37 does not deflect too far down and thereby collides with the package to be strapped. It is primarily a sideways movement of the lower part 37 is desired, but at the same time a lateral opening of the bypass channel 28, so that the belt loop 16 by the thrust element not shown in the direction the Bandein- and outlet channel 29 is displaced. Fig. 17 shows the position of the belt loop 16 after it has been pushed out of the bypass channel 28. It is located at a parallel distance from the belt loop 15 in the belt inlet and outlet channel 29. The distance is possible not greater than 3 mm. So that the belt loop 16 does not jam when pushed out of the bypass channel 28, the side walls of the bypass channel 28 may be bevelled. In Fig. 17 are corresponding inclined surfaces 39, 40 to recognize both the upper part 36 and the lower part 37.

The pivot mechanism 38 comprises in this embodiment, a piston-cylinder unit 41, which is in particular a pneumatic cylinder. The entire strapping process is fully automatic. For this purpose, actuators, sensors and the necessary control means are provided in a manner not shown.

Claims (16)

1. A method for applying flat strapping bands (17) made of a plastic or metallic material around packages (5) by means of a strapping machine (12) with the following steps:

   a) the package (5) to be strapped is brought into a strapping position of a strapping device (12);

   b) a band starting end (31) of the strapping band (17) is transported proceeding from a closure head (4) positioned on the package (5) into a first band guide channel (13) which surrounds the package (5);

   c) the band starting end (31) is transported from the end of the first band guide channel (13) into a second band guide channel (14) which follows the latter and which surrounds the package (5);

   d) the band starting end (31) is fed from the end of the second band guide channel (14) to the closure head (4, 30) and is held there;

   e) an intersection point (K) of the first and second band guide channel (13, 14) lying opposite the closure head (4, 30) is freed in order to reduce the size of the band loops (15, 16) intersecting at the intersection point (K) by retracting the strapping band (17) into the closure head (4, 30) until a pre-adjusted tensile force of the strapping band (17) is reached;

   f) connection of the band starting end (31) to the retracted strapping band (17) and severing of the excess strapping band (17) from the supply roll.
2. The device according to claim 1, characterised in that the inner band guide channel (13) is split, at least one of its sub-sections (18, 19) being moved out of the intersection point (K).
3. The method according to claim 1, characterised in that the band guide channels (26, 27) are connected to one another at the intersection point (K), there being formed in the intersection part (21) an inner band channel (22) facing towards the package (5) and an outer band channel (23) running at a greater distance from the package (5), through which band channels the band end (31) is passed once in each case during the strapping, wherein a slider (25) separating the inner band channel (22) with respect to the outer band channel (23) is opened before the retraction of the strapping band (17), in order to pull the strapping band (17) out of the outer band channel (23) in the direction of the package (5).
4. The method according to any one of claims 1 to 3, characterised in that the band starting end (31), after leaving the first band guide channel (26), is passed through a bypass channel (26) running along the closure head (4, 30), said bypass channel emerging into the second band guide channel (27).
5. The method according to claim 4, characterised in that, after the application of the band loops (15, 16), the bypass channel (28) is opened and the band loop (16) is displaced out of the bypass channel (28) in the direction of the band inlet and outlet channel (29) of the closure head (4, 30).
6. The method according to claim 5, characterised in that the laterally displaced band loop (16), after being displaced, is prevented by at least one locking element (33) from travelling back into the bypass channel (28).
7. The method according to any one of claims 1 to 6, characterised in that the band starting end (31) is connected inside the closure head (4, 30) to the band end of the strapping band (17) in a firmly bonded, keyed manner by direct pressing or by using closure sleeves.
8. A strapping device for applying flat strapping bands (17) made of a plastic or metallic material around packages (5), comprising

   a) a closure head (4, 30) which can be positioned with respect to a package (5) to be strapped, wherein the closure head (4, 30) comprises means for tightening the delivered strapping band (17) by partial retraction into the closure head (4, 30) until a pre-adjusted tensile force is reached, connecting the band starting end (31) to the end of the band and severing the end of the band from a supply roll;

   b) a first band guide channel (26, 13), which follows on from a band inlet and outlet channel (29) of the closure head (4, 30) and which surrounds the package (5);

   c) a second band guide channel (27, 14), which follows on from the first band guide channel (26, 13) and which surrounds the package (5) and emerges into a band inlet and outlet channel (29) of the closure head (4, 30);

   d) an intersection point (K) of the band guide channels (26, 27, 13, 14), which lies opposite the closure head (4), which is closed for the pushing-through of the band starting end (31) and which is opened during the tightening of the strapping band (17),

   e) a controlled unit for controlling the drive means of the strapping device.
9. The strapping device according to claim 8, characterised in that the inner band guide channel (13) adjacent to the package (5) is split and comprises therefrom at least one sub-section (18, 19) which can be moved out of the intersection point (K).
10. The strapping device according to claim 9, characterised in that each of the sub-sections (18, 19) is mounted in a swivellable manner.
11. The strapping device according to claim 8, characterised in that the band guide channels (26, 27) are connected to one another at the intersection point (K) by an intersection part (21), wherein an inner band channel (22) facing towards the package (5) and an outer band channel (23) running at a greater distance from the package (5) are formed in the intersection part (21), wherein a slider (25) separating the inner band channel (22) from the outer band channel (23) is provided.
12. The strapping device according to claim 11, characterised in that the slider (25) is configured U-shaped and forms a sub-section of the inner band channel (22).
13. The strapping device according to claim 11 or 12, characterised in that a bypass channel (28) connected to the end of the first band guide channel (26) and the beginning of the second band guide channel (27) and running along the closure head (4) is provided.
14. The strapping device according to claim 13, characterised in that the bypass channel (28) comprises means for opening a side wall of the bypass channel (28) facing towards the band inlet and outlet channel (29).
15. The strapping device according to claim 14, characterised in that at least one thrust element (32) is provided in order to displace the strapping band (17) out of the bypass channel (28) in the direction of the band inlet and outlet channel (29).
16. The strapping device according to claim 15, characterised in that at least one locking element (33) is provided, which holds the displaced band loop (16) of the strapping band (17) outside the bypass channel (28) when the thrust element (32) is withdrawn.

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