DEVICE FOR SHRINKING A HOT-SHRINK FILM PLACED AROUND A, PREFERABLY PALLETIZED, STACK OF GOODS AND METHOD FOR SHRINKING A HOT-SHRINK FILM PLACED AROUND A, PREFERABLY PALLETIZED, STACK OF GOODS

Abstract

A device for shrinking a heat-shrink film placed around a palletized stack of goods includes a shrinking frame movable on a rack in vertical direction and forming an opening for the stack of goods. A shrinking device for shrinking the heat-shrink film includes a surrounding side wall, forming a shrinking space, comprising a shrink hood open downward and a cover. The shrink hood is movable in the vertical direction, and includes a blower that generates an air flow in the interior of the shrink hood. The blower includes an impeller driven by a drive. At least one air-guide section includes a nozzle on its end opposite the impeller, so that the air suctioned by the impeller from the shrinking space surrounded by the shrink hood can be reintroduce in a directed manner via the nozzle into the shrinking space surrounded by the shrink hood.

Claims

1. Device (1) for the shrinking of a heat-shrink film (3) placed around a preferably palletize, stack of goods (2), with a shrinking frame (5), movable on a rack (4) in vertical direction between an upper position and a lower position, forming an opening (19) for the stack of goods (2), on which at least one shrinking device for the shrinking of the heat-shrink film (3) is provided, wherein the device (1) includes a surrounding side wall (7), forming a shrinking space, comprising a shrink hood (6) open downward, as well as a cover (8), wherein the shrink hood (6) is movable in the vertical direction, and wherein the device (1) furthermore includes at least one blower (9) that generates an air flow in the interior of the shrink hood (6), wherein the at least one blower (9) includes an impeller (20) driven by a drive (10), wherein on the impeller of at least one blower (9) at least one air-guide section (11) is connected, which includes at least one nozzle (12) on its end opposite the impeller (20) so that the air suctioned by the impeller (20) from the shrinking space surrounded by the shrink hood (6) can be reintroduce in a directed manner via the at least one nozzle (12) into the shrinking space surrounded by the shrink hood.

2. A device (1) according to claim 1, wherein at least one nozzle (12) is configured as a slotted nozzle.

3. A device (1) according to claim 1, wherein at least one blower (9) is configured as a radial blower.

4. A device (1) according to claim 1, wherein the impeller (20) of at least one blower (9), and the air-guide section (11) emanating therefrom, are attached below the cover (8) of the shrink hood (6), or are attached indirectly or directly to the inner side of the cover (8) of the shrink hood (6).

5. A device (1) according to claim 1, wherein in at least one air-guide section (11), at least one heating element is provided to heat the air flowing through this air-guide section (11).

6. A device (1) according to claim 1, wherein with at least one blower (9), the assembly comprised of the impeller (20), the air-guide section (11), and the at least one nozzle (12) is designed as horizontally movable.

7. A device (1) according to claim 1, wherein sigh at least one blower (9) the at least one nozzle (12) is configured as horizontally movable, and the length of the air-guide section (11) is variable according to the respective position of the at least one nozzle (12).

8. A device (1) according to claim 1, wherein with at least one blower (9) at least one nozzle is vertically transportable.

9. A device (1) according to claim 1, wherein with at least one blower (9), at least one nozzle (12) is disposed as swivelable about a horizontal axis (18).

10. A device (1) according to claim 1, wherein the device (1) has a closure surface (13) that is adapted with respect to its contour and its dimensions to the contour and the dimensions of the opening (19) of the shrinking frame (5) such that the closure surface (13) on the one hand, and the shrink hood (6) on the other hand, are movable relative to one another, wherein when the shrinking frame (5) is located in its upper position, the closure surface (13) is disposed, preferably stationarily, inside the opening (19), so that with increasing movement of the shrinking frame (5) into its lower position the closure surface (13) moves closer to the cover (8) of the shrink hood (6).

11. A device (1) according to claim 1, wherein the height of the shrinking frame is at least 300 mm higher than the height of a stack of goods (2) to be packaged.

12. A device (1) according to claim 1, wherein the shrink hood (6) is connected with the shrinking frame (5), preferably in an airtight manner.

13. A device (1) according to claim 1, wherein with at least one blower (9), the impeller (20) is enclosed in a housing (21) including a suction intake opening (22), wherein at least one ventilation section (11) is connected to the housing (21).

14. Method for shrinking a heat-shrink film (3) placed around a preferably palletized stack of goods (2), preferably using a device (1), with a shrinking frame (5), movable in vertical direction between an upper position and a lower position, forming an opening (19) for the stack of goods (2), on which at least one shrinking device is provided for shrinking the heat-shrink film (3) by heating, wherein the device (1) includes a surrounding side wall (7), forming a shrinking space, comprising a shrink hood (6) open downward, as well as a cover (8), wherein the shrink hood (6) is movable in vertical direction, and wherein the device (1) furthermore includes at least one blower (9) generating an air flow in the interior of the shrink hood (6), wherein the at least one blower (9) includes an impeller (20) driven by a drive (10), particularly preferably using a device (1) according to one of the preceding claims, wherein on the impeller of at least one blower (9) at least one air-guide section (11) is connected, which includes at least one nozzle (12) on its end opposite the impeller (20) so that the air in the shrinking space enclosed by the shrink hood that is suctioned out by the impeller (20) (6) is reintroduced in a targeted via the at least one nozzle (12) into the shrinking space surrounded by the shrink hood.

15. Method for shrinking a heat-shrink film (3) according to claim 14, wherein the air in the shrinking space surrounded by the shrink hood (6) that is suctioned out by the impeller (20) is reintroduced in a directed manner via the at least one nozzle (12) formed as slotted nozzle into the shrinking space surrounded by the shrink hood (6).

16. Method for shrinking a heat-shrink film (3) according to claim 14, wherein with at least one blower (9), the assembly comprised of the impeller (20), the air-guide section (11), and the at least one nozzle (12) is moved horizontally.

17. Method for shrinking a heat-shrink film (3) according to claim 14, wherein with at least one blower (9), the at least one nozzle (12) is moved horizontally, and the length of the air-guide section (11) varies according to the respective position of the at least one nozzle (12).

18. Method for shrinking a heat-shrink film (3) according to claim 14, wherein with at least one blower (9) at least one nozzle is moved vertically.

19. Method for shrinking a heat-shrink film (3) according to claim 14, wherein with at least one blower (9), at least one nozzle (12) is swivelable about a horizontal axis (18).

20. Method for shrinking a heat-shrink film (3) according to claim 14, wherein with at least one air-guide section (11), at least one heating element is provided, and at least one heating element heats the air flowing through this air-guide section (11).

21. Method for shrinking a heat-shrink film (3) according to claim 14, wherein the device (1) has a closure surface (13) that is adapted with respect to its contour and its dimensions to the contour and the dimensions of the opening (19) of the shrinking frame (5) such that the closure surface (13) on the one hand, and the shrink hood (6) on the other hand, are moved relative to one another, wherein when the shrinking frame (5) is located in its upper position, the closure surface (13) is disposed, preferably stationarily, inside the opening (19), so that with increasing movement of the shrinking frame (5) into its lower position, the closure surface (13) moves closer to the cover (8) of the shrink hood (6).

22. Method for shrinking a heat-shrink film (3) according to claim 14, wherein in the lower position of the shrinking frame (5), the distance A between the top side of the stack of goods (2) and the cover (8) of the shrinking frame (6) is at least 300 mm.

23. Method for shrinking a heat-shrink film (3) according to claim 14, wherein during shrinking, preferably during upper shrinking, at least one nozzle (12) is directed onto the adjacent upper edge (17) of the stack of goods (2).

24. Method for shrinking a heat-shrink film (3) according to claim 14, wherein during shrinking, preferably during upper shrink-wrapping, an air flow is directed via at least two opposing nozzles (12) onto two opposing upper edges (17) of the stack of goods (2).

25. Method for shrinking a heat-shrink film (3) according to claim 14, wherein during shrinking, preferably during the upper shrink-wrapping, at least one nozzle (12) is set in a pendulum motion about its horizontal axis (18).

Description

[0042] In the following, exemplary embodiments of the invention shown in the drawings are explained. They show:

[0043] FIG. 1 an oblique view of an exemplary embodiment of an inventive device,

[0044] FIG. 2 a sectional view of the object of the invention according to FIG. 1, in which the shrinking frame and the shrink hood are located in the upper position,

[0045] FIG. 3 the object according to FIG. 2, in which the shrinking frame and the shrink hood are located in the lower position,

[0046] FIG. 4 a sectional view of an additional exemplary embodiment of the inventive device with a closure surface, in which the shrinking frame and the shrink hood are located in the upper position,

[0047] FIG. 5 the object according to FIG. 4, in which the shrinking frame and the shrink hood are located in the lower position,

[0048] FIG. 6 a sectional view of a further exemplary embodiment of the inventive device with a closure surface in which the shrinking frame and the shrink hood are located in the upper position,

[0049] FIG. 7 the object according to FIG. 6, in which the shrinking frame and the shrink hood are located in the lower position,

[0050] FIG. 8 a sectional view of a further exemplary embodiment of the inventive device with a closure surface and with swivelable slotted nozzles, in which the shrinking frame and the shrink hood are located in the upper position,

[0051] FIG. 9 a view of the inner side of a cover of a shrink hood, and

[0052] FIG. 10 the object according to FIG. 4 with slotted nozzles moved closer together horizontally.

[0053] In all figures, corresponding reference numbers are used for identical or functionally identical components.

[0054] FIG. 1 shows a device 1 for shrinking a not-shown heat-shrink film 3 around a stack of goods 2, also not shown. The device 1 comprises a rack 4 with a shrinking frame 5 movable between an upper position and a lower position. The shrinking frame 5 is comprised of four frame parts forming a rectangular opening 19.

[0055] On each frame part, a shrinking device, not shown in this Figure, is provided for shrinking the heat-shrink film 3 by heating. The device 1 also comprises a shrink hood 6, open downward, forming a shrinking space. The shrink hood 6 here is formed with a side wall 7 and a cover 8. In the exemplary embodiment shown, the shrink hood 6 is connected with the shrinking frame 5 and thus forms a unit with the shrinking frame 5. Here, with vertical shifting of the shrinking frame 5 the shrink hood 6 is moved with it. The device 1 further comprises two blowers 9 respectively generating an air flow in the interior of the shrink hood 6, said blowers 9 each including an impeller 20 driven by a drive 10. The impeller 20 of each blower 9 is situated in the interior of the shrink hood 6, while the respective drive 10 is disposed on the outer side of the shrink hood 6. In the exemplary embodiment shown, each impeller 20 is enclosed by a housing 21, each housing 21 having a suction inlet 22 on its underside.

[0056] FIG. 2 shows a sectional view of the object according to FIG. 1. The shrink hood 6 is connected with the shrinking frame 5 in an airtight manner. The shrinking frame 5 is located in its upper position. The shrinking frame 5 forms the opening 19 for the stack of goods 2. The stack of goods 2 has an underside, by which the stack of goods 2 is set down on a pallet 23, four side surfaces, and a top side. Furthermore, the stack of goods 2 has an edge 17 at the transition from each side surface to the top side.

[0057] The shrinking devices are disposed around the opening 19; in the exemplary embodiment shown, the shrinking devices each include at least one slotted blow-out nozzle 24, which is directed obliquely downward to discharge heated air to shrink the heat-shrink film 3.

[0058] The rack 4, not depicted, of the device 1 is located behind the shrink hood 6 or the stack of goods 2, and stands on a base 15. Centered under the shrink hood 6, the stack of goods 2 is depicted with the heat-shrink film 3. On the inner side of the cover 8 the housing 21 is arranged with the respective impeller 20 located therein. An air-guide section 11 respectively connects to each impeller 20, that is, to each housing 21. On its end opposite the impeller 20, each air-guide section 11 respectively includes a nozzle 12.

[0059] The air suctioned by the impeller 20 via the respective suction outlet opening 22 out of the shrinking space enclosed by the shrink hood 6 is reintroduced in a targeted manner via the respective nozzle 12 into the shrinking space enclosed by the shrink hood 6. In the position shown, the lower edge of the shrinking frame 5 is higher than the top side of the stack of goods 2. Thus, in the state of motion shown, the shrinking process has not yet begun.

[0060] FIG. 3 shows a further state of motion of the object according to FIG. 2. The lower edge of the shrinking frame 5 is now below the stack of goods 2 at the height of a pallet 23. The shrinking frame 5 has accordingly been moved from its upper position into its lower position. In the interior of the shrink hood 6, the heated air discharged by the blow-out nozzles 24 shrinks the heat-shrink foil 3. The blowers 9 simultaneously suction air in the direction of the arrows 25 from the upper region of the shrinking frame into the interior of the shrink hood 6. Via the respective air-guide section 11, the suctioned air is then reintroduced in a targeted manner via the nozzles 12 in the direction of the arrows 26 to the shrinking space enclosed by the shrink hood 6. In the exemplary embodiment shown, each of the two nozzles 12 is configured as a slotted nozzle. The orientation of the slotted nozzles is such that in the lower position of the shrinking frame 5, the discharged air is blown in the direction of the arrows 26 onto the adjacent edges 17 of the stack of goods 2.

[0061] As can be seen in FIG. 3, in the lower position of the shrinking frame 5, the spacing A between the top side of the stack of goods 2 and the cover 8 of the shrink hood 6 is at least 300 mm.

[0062] FIG. 4 shows a sectional view of a further exemplary embodiment of the inventive device 1. The device 1 shown differs from the device 1 shown in FIG. 2 only in that it includes a closure surface 13 that is adjusted with respect to its contour and its dimensions to the contour and the dimensions of the opening 19 of the shrinking frame 5. The closure surface 13 on the one hand and the shrinking frame 5 and the shrink hood 6 on the other hand are movable relative to one another. The shrinking frame 5 forms the opening 19 for the stack of goods 2 and is seen in its upper position. The closure surface 13 is located inside the opening 19 of the shrinking frame 5 and is disposed such that with increasing movement of the shrinking frame 5 into its lower position, the closure surface 13 approaches the cover 8 of the shrink hood 6.

[0063] The closure surface 13 has feet 14, its underside standing with the feet on the base 15. With respect to its contour and dimensions, the closure surface 13 is adapted to the opening 19 such that a gap still remains between the outer edge of the closure surface 13 and the inner edge of the opening 19. The closure surface 13 reduces heat loss when the shrinking frame 5 is located in its upper position. The closure surface 13 is also disposed at a height where, on the one hand, it is above the stack of goods 2, and on the other hand essentially closes off the shrinking frame 5 on its underside. Due to the closure surface 13, the opening 19 of the shrinking frame 5, and thus the shrinking space of the shrink hood 6, is nearly closed off, except in the region of the gap described above.

[0064] In FIG. 5, the lower edge of the shrinking frame 5 is now disposed lower than the underside of the stack of goods 2. The shrinking frame 5 has accordingly been moved from its upper position into its lower position. In the interior of the shrink hood 6, the air heated by the shrinking device shrinks the heat-shrink film 3. The two blowers 9 in turn suction air out of the upper region of the shrinking space in the interior of the shrink hood 6 in the direction of the arrows 25 and guide it via the respectively connected air-guide sections 11 to the nozzles 12. Via the nozzles 12, the warm air is reintroduced in a targeted manner in the direction of the arrows 26 into the shrinking space enclosed by the shrink hood 6. In the exemplary embodiment shown, each of the two nozzles 12 is configured as a slotted nozzle. The orientation of the slotted nozzles is such that in the lower position of the shrinking frame 5, the discharged air is blown in the direction of the arrows 26 onto the adjacent edges 17 of the stack of goods 2. Due to the lowering of the shrinking frame 5 and thus also of the shrink hood 6, the closure surface 13 has moved into the interior of the shrink hood 6. The feet 14 do not impede the airflow directed by the nozzles 12, since they are arranged such that they do not partially cover the respective slotted nozzle.

[0065] FIG. 6 shows a sectional view of a further exemplary embodiment of the inventive device 1. The device 1 shown differs in this respect from the device shown in FIG. 4 only in that the closure surface 13 is now suspended on rods 16; the rods 16 pass through the cover 8 of the shrink hood 6, and are attached to the rack 4. The rack 4 stands on the base 15. The closure surface 13 on the one hand, and the shrinking frame 5 and the shrink hood 6 on the other hand, are movable relative to one another. The shrinking frame 5 forms the opening 19 for the stack of goods 2, and is located in its upper position. The closure surface 13 is located inside the opening 19 of the shrinking frame 5 and is arranged such that with increasing movement of the shrinking frame 5 into its lower position, the closure surface 13 moves closer to the cover 8 of the shrink hood 6.

[0066] FIG. 7 shows the position in which the lower edge of the shrinking frame 5 is disposed lower than the underside of the stack of goods 2. The shrinking frame 5 has accordingly been moved from its upper position into its lower position. This is in turn the start of the shrinking process, in which the shrinking frame is moved vertically upward. In the interior of the shrink hood 6, the air heated by the shrinking device shrinks the heat-shrink film 3. The blowers 9 suction air out of the upper region of the shrinking space in the interior of the shrink hood 6 in the direction of the arrow 25 and guide it via the respectively connected air-guide section 11 to the nozzle 12. Via the respective nozzle 12, the warm air is blown again in a targeted manner in the direction of the arrows 26 into the shrinking space enclosed by the shrink hood 6. In the exemplary embodiment shown, each of the two nozzles 12 is formed as a slotted nozzle. The orientation of the slotted nozzles is such that in the lower position of the shrinking frame 5, the expelled air is blown in the direction of the arrows 26 onto the adjacent edges 17 of the stack of goods 2.

[0067] FIG. 8 shows a sectional view of an additional exemplary embodiment of the inventive device 1. The device 1 shown here differs from device 1 according to FIG. 4 only in that the nozzles 12 are disposed as swivelable about a horizontal axis 18. Each nozzle 12 can be swiveled, for example, with an electric motor that is not shown. The swiveling of each nozzle 12 enables the precise orientation of each nozzle 12 toward the respective edge 17 of a stack of goods 2. This adjustment can also take place during the vertical displacement of the shrinking frame 5. In this way, the edges 17 of stacks of goods 2 of different height can also be shrunk with optimal effectiveness.

[0068] FIG. 9 shows a view of the underside of the cover 8 of the shrink hood 6. Each of the two impellers 20 is enclosed by a housing, each housing 21 having the suction intake opening 22 on its underside. The air-guide section 11 is connected to each impeller 20, that is to each housing 21 respectively. Each air-guide section 11 has the nozzle 12 on its end opposite the respective impeller 20. Each nozzle 12 is configured as a slotted nozzle.

[0069] In FIG. 9, the distance between the two nozzles 12 is greater than in FIG. 10. This is due to the fact that in FIG. 10, the two nozzles 12 which are movable horizontally in the direction of the arrow 27, have been moved toward each other. In order to enable this movement of the nozzles 12, the length of each air-guide section 11 is variable according to the respective position of the respective nozzle 12. Thus each air-guide section 11 can be configured as telescopable, for example, Thus, despite the fixed position of an impeller 20, the corresponding nozzle 12 can be moved horizontally in the direction of the arrow 27. Thus each nozzle 12 can be optimally positioned, for example, with respect to the respective edge 17. In addition, it is also possible for each nozzle 12 to still be swivelable about a horizontal axis.

[0070] Alternatively, with one blower 9, the entire assembly comprised of the impeller 20, the housing 21 that encloses it, the air-guide section 11, and the nozzle 12 can also be designed as horizontally movable as a unit in the direction of the arrow 27.