METHOD AND DEVICE FOR FLEXIBLE STRAPPING

Description

[0001] The invention relates to a device for strapping packaged goods with a strapping band, comprising a band guide frame to which strapping band is fed to form a loop around the packaged goods, wherein the band guide frame has an upper horizontal section which is formed by a horizontally displaceable and height-adjustable lance which can be displaced from a strapping position closing the band guide frame into an open position outside the band guide frame.

[0002] Such a device is described in DE 10 2019 118 307 A1 by the applicant. This document proposes for the first time to equip a machine for strapping packaged goods arranged on pallets with two horizontally movable lances, each of which is provided with its own insertion drive so that it can be moved separately into the strapping position, in which the lances form the horizontally extending sections of the strap guide frame, or into the open position, in which they are located outside the strap guide frame. It is also mentioned here that each lance can be assigned at least one height adjustment device for adjusting its height. This document does not contain any further details on the design of the height adjustment device and, in particular, on the combination of a height-adjustable lance with other sections of the strap guide frame.

[0003] The object of the invention is to provide a strapping device with a strap guide frame which functions reliably with an adjustable height of the displaceable upper horizontal section of the strap guide frame.

[0004] This object is achieved according to the invention in that a first vertical section of the strap guide frame has a plurality of pivot segments arranged one above the other and in that the lance is coupled to a vertically acting travel drive which is designed to align the lance to one of the pivot segments before it is pushed horizontally into the strapping position.

[0005] In other words, the vertical section of the belt guide frame, through which the lance can be inserted at different heights to form the upper horizontal section of the belt guide frame, is provided with a plurality of pivoting segments. The pivoting segments can pivot when the lance is inserted to allow the lance to pass through. The pivoting segments can be arranged directly one after the other. However, it is also possible to arrange several, e.g. three or four, pivoting segments at three or four discrete heights of the vertical section of the belt guide frame. In this case, the lance can only be moved to the predetermined three or four higher positions in which the three or four pivoting segments are located.

[0006] In a practical embodiment, the plurality of pivot segments can be coupled to a lifting drive that can vertically displace the pivot segments at least by the amount of their height. Such a lifting drive ensures that the lance can be continuously moved to any desired height position and not just to predetermined, discrete positions of the pivot segments. In this embodiment, a segment section that extends over the desired vertical travel range of the lance and has, for example, six to 10 pivot segments arranged directly above one another can form a specific part, in particular the upper part of the first vertical section of the belt guide frame. This segment section can then be coupled to the lifting drive so that this lifting drive raises or lowers all pivot segments together. Each pivot segment must have a height that corresponds at least to the height of the displaceable lance.In a practical embodiment, a first corner guide element can be attached to the lance, which forms the upper end of the vertical section of the belt guide frame when the lance is inserted and can be pushed through the first vertical section of the belt guide frame with the lance in the area of ​​one of the pivoting segments. In this embodiment, the height of each pivoting segment must correspond to the entire height of the lance with the first corner guide element attached to it. Each of the pivoting segments defines a height position into which the lance can be inserted. The higher positions have a vertical distance from the adjacent height position that corresponds to the height of a pivoting segment.Since the position of the segment section with the swivel segments can be moved by the lifting drive over a distance that corresponds at least to the height of a swivel segment, the lance can be arranged at any height position in the area of ​​the segment section, whereby the lifting drive aligns the nearest swivel segment to the height of the lance.

[0007] In practice, the lance can be coupled to a slide-in drive that moves the lance horizontally, and the travel drive for the vertical movement of the lance is coupled to the slide-in drive in order to move it vertically together with the lance.

[0008] In practice, each pivoting segment can have a guide surface for the strapping on the side facing the inside of the strap guide frame, which is covered by at least one pivoting flap. A strap guide frame usually has a strap guide channel in which the strapping is guided with minimal play. The uninterrupted guidance of the strapping on the outer contact surface of the strap channel is of great importance. Particularly in the area of ​​the corner guide element, where the strapping changes its feed direction, it is pressed outwards by mass inertia against the outer surface of the strap guide channel, which is farther away from the center of the strap guide frame. It is also important, however, that the strapping is guided towards the inside of the strap guide frame. On the other hand, the strap loop formed in the strap guide frame must be able to be pulled out of the strap channel in order to be tensioned around the packaged goods.For this purpose, the strap guide frame is equipped with pivoting flaps that swing open when the strap loop is pulled tight by the strapping, releasing the strap. To ensure reliable guidance of the strapping in the area of ​​the pivoting segments of the strap guide frame, each pivoting segment can be equipped with corresponding pivoting flaps. It is possible to have a pivoting flap attached to one side of the pivoting segment. However, two pivoting flaps can also be provided on the two sides of a pivoting segment. When the strap loop is pulled tight, the pivoting segments swing open and release the strap channel.

[0009] If, however, the pivoting movement of the pivoting segment for allowing the lance to pass through shifts a band channel provided in the pivoting segment and open on a narrow side into a position in which the band can exit from the band channel when the loop is pulled together, pivoting flaps on the pivoting segment can be dispensed with.

[0010] In practice, a second vertical section of the strap guide frame can have a second corner guide element that has a receiving area for receiving the free end of the lance in the strapping position. As already explained above, the corner guide elements serve to direct the direction of movement of the strapping when transitioning from a vertical section to a horizontal section of the strap guide frame and vice versa. The first corner guide element, which interacts with the first vertical section of the strap guide frame when the lance is retracted, is attached to the lance. The second corner guide element, which interacts with the free end of the lance, is attached to the second vertical section of the strap guide frame. So that the second corner guide element can be aligned to the selected height of the lance, a height adjustment drive is coupled to the second corner guide element.

[0011] The height adjustment drive and the travel drive can be coupled together in the following way to align the height of the second corner guide element to the height of the lance. A mechanical coupling can be provided so that a mechanical coupling means effects a corresponding vertical height adjustment of the second corner guide element when the lance is moved vertically. In the simplest case, the travel drive can adjust the height of the lance and be coupled to the corner guide element via a flexible drive means, for example, a chain or a toothed belt. This engagement means then forms the height adjustment drive, which always adjusts the height of the corner guide element synchronously with the height of the lance.An electronic coupling can be provided, whereby the height of the lance is determined by a measuring device and the height adjustment drive is controlled via a control device such that the second corner guide element is moved to the appropriate height. The measuring device can, for example, be an optical measuring device that measures the set height of the lance. Furthermore, increments and light barriers can be used to measure the height adjustment of the lance. Finally, when using stepper motors, it is also possible to use signals from the motors themselves to determine the height adjustment. Stepper motors can be equipped with a signal generator that generates signals corresponding to the angle of rotation of the motor shaft. This can be used to determine relative values ​​for the height adjustment. Such stepper motors can then be connected to limit switches that indicate when the lance has reached an end position.The control electronics for the height adjustment drive then ensures that the height of the corner guide element is aligned to the set height of the lance.

[0012] In practice, the lower horizontal section of the belt guide frame can be formed either by a second horizontally movable lance or by a stationary lower frame section. In other words, the belt guide frame can consist of a rigid, U-shaped frame section, with a horizontally and vertically movable lance provided only in the upper area. Alternatively or additionally, it is also possible to provide a horizontally movable lance in the lower area. This is particularly advantageous if the lower horizontal section of the belt guide frame is intended to extend through a pallet, as described in DE 10 2019 118 307 A1.

[0013] The invention further relates to a method for strapping packaged goods with a strapping band, in which a strapping band is fed to a band guide frame to form a loop around the packaged goods, wherein the band guide frame has an upper horizontal section which is formed by a horizontally displaceable and height-adjustable lance which is displaced from an open position outside the band guide frame into a strapping position closing the band guide frame.

[0014] To achieve the above object, it is proposed that a first vertical section of the strap guide frame has a plurality of swivel segments arranged one above the other and that the lance is aligned with one of the swivel segments by means of a vertically acting travel drive before being inserted horizontally into the strapping position.

[0015] As mentioned, the multiple swivel segments can be coupled to a lifting drive, which moves the swivel segments vertically to a desired position when required.

[0016] The lance can be coupled to a slide-in drive that moves the lance horizontally, and the travel drive can engage the slide-in drive to move it vertically.

[0017] As mentioned above, a first corner guide element can be attached to the lance, which forms the upper end of a vertical section of the belt guide frame when the lance is inserted and is pushed through the first vertical section of the belt guide frame with the lance in the region of one of the pivoting segments.

[0018] Furthermore, a second vertical section of the strap guide frame can include a second corner guide element having a receiving area for receiving the free end of the lance in the strapping position. A height adjustment drive is coupled to the second corner guide element and aligns the second corner guide element to the height of the lance. The coupling can be mechanical or electronic, as described above.

[0019] Further practical embodiments and advantages of the invention are described below in conjunction with the drawings. They show: Fig. 1 is a three-dimensional view of a strapping device for pallets with packaged goods according to the prior art; Fig. 2 is a side view of a strap guide frame according to the invention; Fig. 3 is a top view of the strap guide frame from Fig. 2 ; Fig. 4 a side view of the tape guide frame from Fig. 2 in open position; Fig. 5 a complete side view of the lances of the belt guide frame from Fig. 4 ; Fig. 6 a first three-dimensional side view of the travel drive for the upper lance from Fig. 5 ; Fig. 7 a second three-dimensional side view of the travel drive for the upper lance from Fig. 5 ; Fig. 8 a first three-dimensional view of the height adjustment drive for a corner guide element of the belt guide frame; Fig. 9 a second three-dimensional view of the height adjustment drive for a corner guide element of the belt guide frame

[0020] In the Fig. 1 The strapping station 1 is shown in the prior art according to DE 10 2019 118 307 A1. In the strapping station 1, there is a bundle consisting of two pallets 2, 3 and packaged goods 4, 5 stacked on them. A support table 6 is shown schematically, on which the lower pallet 2 is placed, for example, using a forklift. In practice, a roller conveyor can alternatively be arranged at the height of the support table 6, which automatically conveys the lower pallet 2 into the strapping station 1.

[0021] A horizontal lance 7 extends through the lower pallet 2. Another lance 8 extends through the upper pallet 3. The pallets can be so-called EURO pallets or WORLD pallets, which have skid boards on the underside and deck boards on the top. The lances 7, 8 extend through a gap between the skid board and the deck board. However, other pallet designs can also be used. The pallets have a free space through which one of the two lances 7, 8 can be guided. Fig. 1 It can be seen that two parallel tape guide frames 9, 10 are provided. Both tape guide frames 9, 10 are constructed identically to each other, so that only the tape guide frame 9, which is located at the front for the viewer, will be described below.

[0022] The lower lance 7 forms the lower leg of the strap guide frame. It has a strap channel, as is known, through which a strapping band can be guided. The strapping band is wound on a strap reel 11. It can be seen that a second strap reel 12 is assigned to the second strap guide frame 10.

[0023] A drive and tensioning unit 13 pulls the strapping band from the band roll 11 and feeds it into the band channel in the lower lance 7. When the band guide frame 9 is in the closed position, the lower lance 7 extends to a corner guide element 20 on the rear, fixed frame member 14, which forms a vertically extending section of the band guide frame 9. A horizontal section of a band channel is arranged in the lance 7. The corner guide element 20 has a concavely curved surface that deflects the strapping band from the horizontal to the vertical direction. The strapping band is guided vertically upwards in the vertical frame member 14. At the top, the strapping band exits the vertical section of the band channel in the vertical frame member 14 and is deflected by an upper corner guide element 21 of the band guide frame 9 in the horizontal direction to the front end of the upper lance 8.The upper lance 8 also has a horizontal section of the strap channel, which guides the strapping through the upper pallet 3 back to the side of the drive and tensioning unit 13. From the strap channel in the lance 8, the strap enters a vertical section 19, which guides the strap back to the drive and tensioning unit 13. The drive and tensioning unit 13 then pulls the strapping back so that the formed strap loop is pulled together and tensioned around the strapped packaged goods. For this purpose, the inside of the strap guide frame 9, 10 has pivoting flaps that open when the strap loop is pulled together and allow the strapping to exit the strap guide channel. The tensioned strap loop is then closed. The drive and tensioning unit 13 also houses the connecting device, which closes the strap loop after the strap loop has been pulled tight and tensioned.For this purpose, two overlapping ends of the strap loop are usually welded together.

[0024] It can be seen that by passing two lances 7, 8 through two pallets 2, 3, a secure and firm connection of the pallets 2, 3 can be created, in particular because belt loops are created by two belt guide frames 9, 10 in two mutually parallel and spaced vertical planes.

[0025] The upper pallet 3 can be strapped in the same way before being placed on the lower pallet 2. In this way, the entire package is fully secured.

[0026] It should be noted that Fig. 1 does not fully show the support structures for all components of the strapping device. For example, no support structure for the insertion drives 15, 16 of the two lances 7, 8 is shown in the Fig. 1 and 2Behind the insertion drives 15, 16 for the two lances 7, 8, support profiles 17, 18 are shown, the fastening of which is also Fig. 1 They are attached to a standard support frame. The components that allow the height adjustment of the upper lance 8 are also missing from the Fig. 1 and are, as explained below, in the Fig. 2 bis 9 shown.

[0027] Fig. 2 shows a side view of a belt guide frame with height adjustment of the upper lance 8. This belt guide frame can replace both the front belt guide frame 9 and the rear belt guide frame 10 in the device from Fig. 1 For reasons of clarity, the packaged goods are Fig. 2-4 Not shown. The positions of pallets 2 and 3 are marked for orientation.

[0028] Especially in the Fig. 2 and 4It can be seen that the upper section of the vertical section 19 of the belt guide frame on the right side is formed by a segment section 22, which has eight consecutive pivot segments 23 arranged vertically one above the other. The pivot segments 23 allow the upper lance 8 to be inserted through the vertical section 19 into the interior of the belt guide frame 9, 10.

[0029] Corner guide elements 24, 25 are also arranged on this vertical section 19 of the strap guide frame 9, 10, which guide the strapping band. The lower corner guide element 25 is permanently installed. The upper corner guide element 24 is attached to the upper lance 8. This is shown in Fig. 5 When the upper lance 8 is inserted into the belt guide frame 9, 10, the upper lance 8 pushes the corner guide element 24 attached to it through the pivot segment 23. Consequently, the height of a pivot segment 23 corresponds to the total height of the upper lance 8 and the corner guide element 24 attached to it. The height of a pivot segment 23 is therefore several centimeters. The height adjustment of the upper lance 8 relative to the segment section 22 is therefore only possible in steps, each of which corresponds to the height of a pivot segment 23.

[0030] To achieve a continuous height adjustment of the upper lance 8, a height adjustment of the segment section 22 can also be provided. The segment section 22 can be vertically displaced within a range that corresponds at least to the height of a pivoting segment 23.

[0031] The Fig. 6 and 7show the parts of an exemplary embodiment of the travel drive 26 for the upper lance 8 and the lifting drive 27 for the segment section 22. The coupling of the travel drive 26 and the lifting drive 27 with the lance 8 and the segment section 22 is shown in the preceding Fig. 2-5 not shown. The travel drive 26 is an electric motor that acts via a gear on a rack 29 that is attached to a support element 30. The support element 30 carries the insertion drive 16 of the upper lance 8. The travel drive 26 can be held by a suitable support frame that is not shown in the figures. With the travel drive 26, the insertion drive 16 with the upper lance 8 coupled thereto can be aligned to the height of one of the swivel segments 23. This is shown, for example, in Fig. 7 can be seen, in which the upper lance 8 is aligned with the third pivot segment 23 from below and this pivot segment 23 is pivoted upwards, wherein the upper lance 8 projects through the vertical plane of the vertical section 19 of the belt guide frame 9, 10 in the height range of this pivoted pivot segment 23.

[0032] The lifting drive 27, in turn, effects a height adjustment of the segment section 22 of the vertical section 19 of the belt guide frame 9, 10. The lifting drive 27 acts on a support frame 31 to which the segment section 22 is attached. The lower end 32 of the segment section 22 is telescopically displaceable relative to the vertical section 19 of the belt guide frame 9, 10 (see Figs. 2 , 4 , 5 ).

[0033] In Fig. 7 The sides of the pivoting segments 23 facing the center of the strap guide frame 9, 10 can be seen. These have a pivoting flap 35 that opens when the strapping band is pulled out of the section of the strap guide channel formed by the respective pivoting segment 23. The pivoting flap 35 can be elastically deformable or rigid and pivotable about an axis. Examples of elastically deformable pivoting flaps are disclosed in DE 10 2014 213 791 A1. Rigid pivoting flaps are known, for example, from DE 25 07 717 C3. Magnetic pivoting flaps 35 are also known, for example, from EP 1 702 844 B1.

[0034] The Fig. 8 and 9show the height adjustment drive 33 for the upper corner guide element 21 of the belt guide frame 9, 10. In the illustrated embodiment, the height adjustment drive 33 is again an electric motor that acts on a threaded rod 34 via a gear transmission. The threaded rod 34 causes a vertical displacement of the corner guide element 21. The height of the upper lance 8 can be measured by a suitable sensor, whereby a control device sets the corresponding height of the corner guide element 21 via the height adjustment drive 33. As an alternative to such an electronic coupling of the height of the lance 8 and the corner guide element 21, a mechanical coupling can of course also be implemented, for example by a chain or a stretch-resistant drive belt indirectly transmitting the movement of the lance 8 to the corner guide element 21.

[0035] It should be noted that the drive means for the height adjustment are provided only as examples. Instead of the electric motors shown, linear drives can also be used for the height adjustment. The movement coupling between the drives and the previously adjusting elements (lance 8 and corner guide element 21, as well as segment section 22) does not have to be achieved via gears, but can be achieved by any other known coupling elements. Finally, it is also possible to make the lower lance 7 height-adjustable using similar drive means if this is required for a specific application.

[0036] The features of the invention disclosed in the present description, the drawings, and the claims may be essential, both individually and in any combination, for the realization of the invention in its various embodiments. The invention is not limited to the described embodiments. It may be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art. Bezugszeichenliste

[0037] 1 Strapping station 2 Lower first pallet 3 Second pallet 4 Packaged goods 5 Packaged goods 6 Support table 7 Lower lance 8 Upper lance 9 First strap guide frame 10 Second strap guide frame 11 First strap reel 12 Second strap reel 13 Drive and tensioning unit 14 Second vertical section, beam 15 Insertion drive of the lower lance 16 Insertion drive of the upper lance 17 Support profile 18 Support profile 19 First vertical section 20 Corner guide element 21 Corner guide element 22 Segment section 23 Swivel segment 24 Corner guide element 25 Corner guide element 26 Travel drive 27 Lifting drive 29 Rack 30 Support element 31 Support frame 32 Lower end of the segment section 33 Height adjustment drive 34 Threaded rod 35 Swivel flap

Claims

1. A device for strapping goods with a strap, having a strap guide frame (9, 10) to which strap is fed to form a loop around the goods (4, 5), the strap guide frame (9, 10) having an upper horizontal section which is formed by a horizontally displaceable and height-adjustable lance (8) which can be displaced from a strapping position closing the strap guide frame into an opening position outside the strap guide frame, characterized in that a first vertical section (19) of the strap guide frame (9, 10) has a plurality of swivel segments (23) arranged one above the other, and in that the lance (8) is coupled to a vertically acting displacement drive (26) configured to align the lance (8) with one of the swivel segments (23) before the horizontal insertion into the strapping position.

2. The device according to claim 1, characterized in that the plurality of swivel segments (23) are coupled to a lift drive (27) which is configured to displace the swivel segments (23) vertically at least by the amount of their height.

3. The device according to claim 1 or 2, characterized in that the lance (8) is coupled to an insertion drive (16) which displaces the lance (8) horizontally, and in that the displacement drive (26) is configured to move the insertion drive (16) vertically.

4. The device according to one of the preceding claims, characterized in that each swivel segment (23) has a guide surface for the strap on the side facing the central region of the strap guide frame (9, 10), which guide surface is covered by at least one swivel flap (35).

5. The device according to one of the preceding claims, characterized in that a first corner guide element (24) is fastened to the lance (8), which corner guide element (24) forms the upper end of a vertical section (19) of the strap guide frame when the lance (8) is inserted and can be pushed with the lance (8) through the first vertical section (19) of the strap guide frame (9, 10) in the region of one of the swivel segments (23).

6. The device according to any one of the preceding claims, characterized in that a second vertical portion (14) of the strap guide frame (9,10) comprises a second corner guide element (21) having a receiving area for receiving the free end of the lance (8) in the strapping position, wherein a height adjustment drive (33) is coupled to the second corner guide element (21) and is configured to align the second corner guide element (21) with the height of the lance (8).

7. The device according to claim 6, characterized in that the displacement drive (26) and the height adjustment drive (33) are coupled to each other for aligning the height of the second corner guide element (21) with the height of the lance (8) in one of the following ways: • by a mechanical coupling means which, when the lance (8) is moved vertically, causes a corresponding vertical height adjustment of the second corner guide element (21); • by electronic coupling means, wherein a measuring device determines the height of the lance (8) and a control device controls the height of the adjustment drive in order to move the second corner guide element (21) to the corresponding height.

8. The device according to any one of the preceding claims, characterized in that the lower horizontal portion of the strap guide frame is formed by any one of the following: • a second horizontally displaceable lance (7); • a stationary lower frame section.

9. A method for strapping goods with a strap, in which a strap is fed to a strap guide frame (9, 10) to form a loop around the goods, the strap guide frame (9, 10) having an upper horizontal section which is formed by a horizontally displaceable and height-adjustable lance (8) which is displaced from an open position outside the strap guide frame (9,10) into a strapping position which closes the strap guide frame (9, 10), characterized in that a first vertical section of the strap guide frame (19) has a plurality of swivel segments (23) arranged one above the other, and in that the lance (8) is aligned with one of the swivel segments (23) by means of a vertically acting displacement drive (26) before being pushed horizontally into the strapping position.

10. The method of claim 9, characterized in that the plurality of swivel segments (23) are coupled to a lift drive (27) that vertically displaces the swivel segments (23) to a desired position when needed.

11. The method according to claim 9 or 10, characterized in that the lance (8) is coupled to an insertion drive (16) which displaces the lance (8) horizontally, and that the displacement drive (26) moves the insertion drive (16) vertically.

12. The method according to one of the preceding claims 9 to 11, characterized in that a first corner guide element (24) is fastened to the lance (8), which corner guide element (24) forms the upper end of a vertical section (19) of the strap guide frame when the lance (8) is inserted, the corner guide element (24) being pushed together with the lance (8) through the first vertical section (19) of the strap guide frame (9, 10) in the region of one of the swivel segments (23).

13. The method according to any one of the preceding claims 9 to 12, characterized in that a second vertical section (14) of the strap guide frame (9,10) comprises a second corner guide element (21) having a receiving area for receiving the free end of the lance (8) in the strapping position, wherein a height adjustment drive (33) is coupled to the second corner guide element (21) and aligns the second corner guide element (21) to the height of the lance (8).

14. The method according to claim 13, characterized in that the displacement drive (26) and the height adjustment drive (33) are coupled together for aligning the height of the second corner guide element (21) with the height of the lance (8) in one of the following ways: • by a mechanical coupling means which, when the lance is moved vertically, causes a corresponding vertical height adjustment of the second corner guide element; • by electronic coupling means, wherein a measuring device determines the height of the lance and a control device controls the height adjustment drive so as to move the second corner guide element to the corresponding height.