Apparatus and method for shrinking heat shrink film placed around stack of goods

Abstract

The invention relates to a device for shrinking a heat shrink film placed around a preferably palletized stack of goods, comprising a shrink frame forming a recess for the stack of goods, at least one shrink device for shrinking the heat shrink film being arranged on the shrink frame, the shrink cover comprises a surrounding side wall and a cover, and the device further comprises a blower, and the blower is provided with an impeller driven by a driver. In order to specify a device capable of thermally loading individual regions of a heat shrink film in the interior of a shrink cover, at least one air guide section is connected to the impeller of at least one blower, which air guide section has at least one nozzle at the end thereof opposite the impeller, the at least one nozzle is arranged such that air sucked by the impeller can be directed again into the contraction space surrounded by the contraction cover via the at least one nozzle. Furthermore, the invention relates to a method for shrinking a heat shrink film placed around a preferably palletized cargo stack.

Description

Technical Field

[0001] The invention relates to a device for shrinking a heat shrink film placed around a preferably palletized stack of goods, the device comprising a shrink frame which can be moved on a frame in the vertical direction between an upper position and a lower position and forms a recess for the stack of goods, the shrink frame being provided with at least one shrinking device for shrinking the heat shrink film by heating, wherein the device comprises a shrink hood which is open downwards and forms a shrinking space above the shrink frame, the shrink hood comprising surrounding side walls and a cover, the shrink hood being movable in the vertical direction, and wherein the device also comprises at least one blower which generates an air flow in the interior of the shrink hood, wherein at least one blower has an impeller driven by a drive. Background Art

[0002] From practice, devices for shrinking heat shrink films placed around a pile of goods are known, which devices include a shrink hood. The air in the shrink hood is circulated by means of a blower in order to achieve a uniform temperature level in the shrink hood. In this regard, the blower only allows the circulation of the air in the shrink hood. Summary of the invention

[0003] The object of the present invention is to avoid the above-mentioned disadvantages and to specify a device which enables a more targeted thermal loading of individual regions of the heat shrink film in the interior of the shrink hood.

[0004] This object is achieved in a device of this type in that at least one air guide section is connected to the impeller of at least one blower, and the air guide section has at least one nozzle at its end opposite the impeller, so that the air sucked in by the impeller in the contraction space surrounded by the contraction hood can be brought back into the contraction space surrounded by the contraction hood in a directed manner via the at least one nozzle.

[0005] Each air guide section connected to the impeller with at least one nozzle forms an air channel through which the heated air sucked by the blower flows. The nozzle concentrates the air flow generated by the corresponding blower on a specific area of ​​the heat shrink film. The heated air volume is taken out from the heated shrink space above the goods pile by the blower and blown out in a targeted and thus directed manner after passing through the air guide section. The direction of the air flow is used to heat the individual areas of the heat shrink film at the surface of the goods pile and thus shrink the corresponding areas of the heat shrink film. In this regard, particular attention is paid to the area in which multiple film layers should be connected. For example, this can be an area in which the jacket film and the cover film (Deckblattfolie) overlap. In this way, a good packaging with high load stability of the packaged goods is obtained. In this regard, the air is sucked from the area above the goods pile by the impeller and blown into the shrink space surrounded by the shrink hood again in a directed manner via at least one nozzle.

[0006] In one possible mode of operation of the device, the shrink frame and therefore also the shrink hood are in the upper position. The shrink space is heated by means of the shrink device(s). Then or even beforehand, the stack of goods with the already arranged heat shrink film and possibly the placed cover film is brought close together, for example by means of a conveyor, until the stack of goods is centrally located below the shrink frame and the shrink hood. Subsequently, the shrink frame and therefore also the shrink hood are displaced vertically downwards into their lower position. The shrink hood with the heated shrink space is thus lowered onto the stack of goods. In this case, the air flow generated by the corresponding blower is directed in a targeted and therefore directed manner toward the desired surface portion of the stack of goods by each nozzle. The shrinking process ends when the shrink frame and the shrink hood reach their lower position. The shrink frame and the shrink hood are displaced again into their upper position and the stack of goods with the shrunken heat shrink film is transported away.

[0007] The shrink frame usually consists of four frame parts forming a quadrilateral recess. The shrink space enclosed by the shrink hood is enlarged by the shrink frame arranged below the shrink hood. The shrink hood is preferably directly connected to the shrink frame, for example to the upper side of the shrink frame, or is arranged on the shrink frame. The shrink hood and the shrink frame can be connected to each other in an airtight manner. The shrink hood preferably consists of a heat-insulating housing. For example, at least one shrink device can be designed as an electrically operated shrink device. Other types of shrink devices are also possible. In this way, the shrink device can also be gas-operated, for example.

[0008] Advantageously, the drive of each blower is arranged outside the shrink hood, while the impeller is arranged inside the shrink hood. On the one hand, such an arrangement can save structural space inside the shrink hood. On the other hand, the drive is not subjected to the high operating temperatures inside the shrink hood.

[0009] It is also possible that the complete blower is arranged inside the shrink hood. However, it is also conceivable that the blower is arranged outside the shrink hood and the air is sucked from the interior of the shrink hood via the opening in the cover. The air guide section can be arranged inside or outside the shrink hood.

[0010] Advantageously, at least one nozzle can be designed as a slot nozzle. Preferably, the slot nozzle extends from one side of the shrink hood to the opposite side and thus extends over the entire edge of the stack of goods to be shrunk. As a result, the edge can be heated uniformly over its entire length. The slot nozzle produces a linearly configured blow jet, which can be optimally directed, for example, toward the edge. The heated air is not directed only in a point-like manner onto the area of ​​the heat shrink film, but rather over the entire length of the edge of the stack of goods.

[0011] Furthermore, at least one blower can be designed as a radial blower. Even in the case of small available installation space, this embodiment makes it possible to arrange the blower or at least the impeller of the blower in the interior of the shrink bell.

[0012] Furthermore, the impeller of at least one blower and the air guide section extending therefrom can be fastened below the cover of the shrink hood and can be fastened indirectly or directly to the inner side of the cover of the shrink hood. By arranging the impeller below the cover of the shrink hood, particularly hot air can be sucked in in the upper region of the shrink hood (i.e. below the cover) and then supplied again in a directed manner.

[0013] Advantageously, at least one heating element for heating the air flowing through the air guiding section can be arranged in at least one air guiding section. The air flowing through the air guiding section can be heated to the temperature required for shrinking by the heating element. In this regard, air having a higher temperature than the temperature normally prevailing inside the shrink hood can be directed in a targeted manner onto the heat shrink film by means of nozzles connected to the air guiding section.

[0014] Furthermore, in at least one blower, the assembly consisting of the impeller, the air guiding section and the at least one nozzle is designed to be horizontally movable. In such a design, the complete assembly is thus horizontally movable.

[0015] Alternatively, in at least one blower, at least one nozzle can be constructed to be horizontally movable, and the length of the air guide section can be varied according to the respective position of the at least one nozzle. For example, the nozzle can be arranged on a carriage that can be moved along at least one track. Other structural designs are also conceivable. The carriage can be equipped with a drive, such as a linear drive. The air guide section can be constructed flexibly (for example as a hose) or at least flexibly in length (for example telescopically).

[0016] Advantageously, in at least one blower, at least one nozzle is vertically movable. For example, the nozzle can be arranged on a carriage that can be moved along a track. The carriage can be equipped with a drive, preferably a linear drive. If the air guide section and the impeller are not also vertically movable together with the nozzle, the air guide section can be designed to be flexible (for example as a hose) or flexible in length (for example telescopic).

[0017] Furthermore, in at least one blower, at least one nozzle can be arranged pivotably about a horizontal axis. The nozzle can be designed pivotably by means of a drive, for example a pneumatic or electric drive. Thus, even in the case of stacks of goods of different sizes, the relevant nozzle can be optimally oriented, for example, toward the edge of the stack of goods. This proves to be advantageous if an increase in heat is required in the region of the edge in order to shrink a plurality of layers.

[0018] In addition, the device can have a closing surface, which is adapted in its contour and its size to the contour and size of the recess of the shrink frame so that the closing surface and the shrink frame and the shrink hood can move relative to each other on the one hand, wherein, when the shrink frame is in its upper position, the closing surface is preferably arranged in a fixed position in the recess so that the closing surface approaches the cover of the shrink hood as the shrink frame gradually shifts into its lower position. For example, the closing surface has a foot and is placed on the ground on the lower side. Alternatively, the closing surface can be fastened to the crossbeam of the frame, for example, by means of a rod. In this case, the rod passes through the cover of the shrink hood. The closing surface is adapted in its contour and size to the recess so that a gap is retained between the outer edge of the closing surface and the inner edge of the recess, so that the closing surface can be displaced relative to the recess preferably without contact. When the shrink frame is in its upper position, the closing surface reduces heat losses. The closing surface is arranged at such a height that it is located on the goods stack on the one hand and the shrink frame is substantially closed at its lower side on the other hand. In this regard, the recess of the shrink frame and thus the shrink space of the shrink hood can be almost closed by the closing surface except in the region of the above-mentioned gap. In this regard, the energy consumption of the device can be significantly reduced by closing the shrink hood or the shrink frame.

[0019] Advantageously, the height of the shrink space can be at least 300 mm higher than the height of the pile of goods to be packaged. The shrink space is enlarged by the shrink frame arranged below the shrink hood. Therefore, when the shrink frame with the shrink hood is in its lower position, a distance of at least 300 mm remains between the upper side of the pile of goods and the lower side of the cover, so that the air sucked in by the impeller in the shrink space surrounded by the shrink hood can be directed again into the shrink space surrounded by the shrink hood via the at least one nozzle.

[0020] Furthermore, the shrink hood can be connected to the shrink frame, preferably in an airtight manner. In such a design, the shrink hood is displaced vertically together with the shrink frame. A connection is understood, for example, to be a design in which the shrink hood is, for example, screwed, riveted or welded directly to the shrink frame. A connection is also understood, for example, to be a variant in which a section of the shrink frame also forms, for example, a lateral part of the shrink hood. The shrink hood can advantageously be connected to the shrink frame in an airtight manner.

[0021] In at least one blower, the impeller can be surrounded by a housing having an intake opening, wherein at least one ventilation section is connected to the housing.

[0022] The invention further relates to a method for shrinking a heat shrink film placed around a preferably palletized stack of goods, preferably using a device having a shrink frame that can be moved on a frame in the vertical direction between an upper position and a lower position and that forms a recess for the stack of goods, at least one shrinking device for shrinking the heat shrink film by heating being arranged on the shrink frame, wherein the device has a shrink hood that is open downwards and forms a shrinking space above the shrink frame, the shrink hood comprising surrounding side walls and a cover, wherein the shrink hood moves in the vertical direction, and wherein the device also has at least one blower that generates an air flow in the interior of the shrink hood, wherein at least one blower has an impeller driven by a drive, particularly preferably when using a device according to one of the aforementioned embodiments.

[0023] Devices for shrinking heat shrink films placed around a pile of goods are known from practice, which devices include a shrink hood. The air in the shrink hood is circulated by means of a blower in order to achieve a uniform temperature level in the shrink hood. In this regard, the blower only allows the circulation of the air in the shrink hood.

[0024] The object of the present invention is to avoid the above-mentioned disadvantages and to specify a method which enables a more targeted thermal loading of individual regions of the heat shrink film in the interior of the shrink hood.

[0025] This object is achieved in a method of this type in that at least one air guide section is connected to the impeller of at least one blower, and the air guide section has at least one nozzle at its end opposite the impeller, so that the air sucked in by the impeller in the contraction space surrounded by the contraction hood is brought back into the contraction space surrounded by the contraction hood in a directed manner via the at least one nozzle.

[0026] Each air guide section connected to the impeller with at least one nozzle forms an air channel through which the heated air sucked by the blower flows. The nozzle concentrates the air flow generated by the corresponding blower on a specific area of ​​the heat shrink film. The heated air volume is taken out from the heated shrink space above the goods pile by the blower, and in this regard is blown out in a targeted and therefore directed manner after the through-flow air guide section. The direction of the air flow is targeted to heat the various areas of the heat shrink film at the surface of the goods pile, and thus shrink the corresponding areas of the heat shrink film. Here, particular attention is paid to the area in which multiple film layers should be connected. For example, this can be an area in which the jacket film and the cover film overlap. In this way, a good packaging with high load stability of the packaged goods is obtained. In this regard, the air is sucked from the area above the goods pile by the impeller and blown into the shrink space surrounded by the shrink hood again in a directed manner via at least one nozzle.

[0027] In one possible mode of operation of the device, the shrink frame and therefore also the shrink hood are in the upper position. The shrink space is heated by means of the shrink device(s). Then or even beforehand, the stack of goods with the already arranged heat shrink film and possibly the placed cover film is brought close together, for example by means of a conveyor, until the stack of goods is centrally located below the shrink frame and the shrink hood. Subsequently, the shrink frame and therefore also the shrink hood are displaced vertically downwards into their lower position. The shrink hood with the heated shrink space is thus lowered onto the stack of goods. In this case, the air flow generated by the corresponding blower is directed in a targeted and therefore directed manner toward the desired surface portion of the stack of goods by each nozzle. The shrinking process ends when the shrink frame and the shrink hood reach their lower position. The shrink frame and the shrink hood are displaced again into their upper position and the stack of goods with the shrunken heat shrink film is transported away.

[0028] The shrink frame usually consists of four frame parts forming a quadrilateral recess. The shrink space enclosed by the shrink hood is enlarged by the shrink frame arranged below the shrink hood. The shrink hood is preferably directly connected to the shrink frame, for example to the upper side of the shrink frame, or is arranged on the shrink frame. The shrink hood and the shrink frame can be connected to each other in an airtight manner. The shrink hood preferably consists of a heat-insulating housing. For example, at least one shrink device can be designed as an electrically operated shrink device. Other types of shrink devices are also possible. In this way, the shrink device can also be gas-operated, for example.

[0029] Advantageously, the drive of each blower is arranged outside the shrink hood, while the impeller is arranged inside the shrink hood. On the one hand, such an arrangement can save structural space inside the shrink hood. On the other hand, the drive is not subjected to the high operating temperatures inside the shrink hood.

[0030] It is also possible that the complete blower is arranged inside the shrink hood. However, it is also conceivable that the blower is arranged outside the shrink hood and the air is sucked from the interior of the shrink hood via the opening in the cover. The air guide section can be arranged inside or outside the shrink hood.

[0031] Advantageously, the air sucked by the impeller in the shrinking space surrounded by the shrinking hood can be directed again into the shrinking space surrounded by the shrinking hood via at least one nozzle configured as a slot nozzle. Here, the slot nozzle preferably extends from one side of the shrinking hood to the opposite side, and thus extends over the complete edge of the pile of goods to be shrunk. Therefore, the edge can be heated uniformly over its entire length. A linearly configured blow-out jet is achieved by the slot nozzle, which can be optimally directed, for example, toward the edge. The heated air is not directed only in a point-like manner to the area of ​​the heat shrink film, but rather to the entire length of the edge of the pile of goods.

[0032] Furthermore, in at least one blower, the assembly consisting of the impeller, the air guiding section and the at least one nozzle can be moved horizontally. In such a design, the complete assembly is thus moved horizontally.

[0033] Alternatively, in at least one blower, at least one nozzle can be horizontally movable, and the length of the air guide section can be varied depending on the respective position of the at least one nozzle. For example, the nozzle can be arranged on a carriage that can be moved along at least one track. Other structural designs are also conceivable. The carriage can be equipped with a drive, such as a linear drive. The air guide section can be constructed flexibly (for example as a hose) or at least flexibly in length (for example telescopically).

[0034] Advantageously, in at least one blower, at least one nozzle is vertically movable. For example, the nozzle can be arranged on a carriage that can be moved along a track. The carriage can be equipped with a drive, preferably a linear drive. If the air guide section and the impeller are not also vertically movable together with the nozzle, the air guide section can be designed to be flexible (for example as a hose) or flexible in length (for example telescopic).

[0035] Furthermore, in at least one blower, at least one nozzle can be pivoted about a horizontal axis. The nozzle can be designed to be pivotable by means of a drive, for example a pneumatic or electric drive. Thus, even in the case of stacks of goods of different sizes, the relevant nozzle can be optimally oriented, for example, toward the edge of the stack of goods. This proves to be advantageous if an increase in heat is required in the region of the edge in order to shrink a plurality of layers.

[0036] Furthermore, at least one heating element can be arranged in at least one air guide section, and the at least one heating element can heat the air flowing through the air guide section. The air flowing through the air guide section can be heated to the temperature required for shrinking by the heating element. In this regard, air having a higher temperature than the temperature normally prevailing inside the shrink hood can be directed in a targeted manner onto the heat shrink film via a nozzle connected to the air guide section.

[0037] Advantageously, the device can have a closing surface, which is adapted to the contour and dimensions of the recess of the shrink frame in terms of its contour and its dimensions, so that the closing surface on the one hand and the shrink frame and the shrink hood on the other hand can move relative to each other, wherein, when the shrink frame is in its upper position, the closing surface is preferably arranged in a fixed position in the recess, so that the closing surface approaches the cover of the shrink hood as the shrink frame gradually shifts into its lower position. For example, the closing surface has feet and is placed on the ground on the lower side. Alternatively, the closing surface can be fastened to the crossbeam of the frame, for example, by means of a rod. In this case, the rod passes through the cover of the shrink hood. The closing surface is adapted to the recess in terms of its contour and dimensions so that a gap is still retained between the outer edge of the closing surface and the inner edge of the recess, so that the closing surface can be displaced relative to the recess preferably without contact. When the shrink frame is in its upper position, the closing surface reduces heat losses. The closing surface is arranged at such a height that it is located on the goods stack on the one hand and the shrink frame is substantially closed at its lower side on the other hand. In this regard, the recess of the shrink frame and thus the shrink space of the shrink hood can be almost closed by the closing surface except in the region of the above-mentioned gap. In this regard, the energy consumption of the device can be significantly reduced by closing the shrink hood or the shrink frame.

[0038] Furthermore, in the lower position of the shrinking frame, the distance A between the upper side of the goods stack and the cover of the shrinking hood is at least 300 mm. Due to the remaining distance A of at least 300 mm between the upper side of the goods stack and the lower side of the cover in the lower position of the shrinking frame and the shrinking hood, each impeller can well suck in the air in the shrinking space surrounded by the shrinking hood and bring it back into the shrinking space surrounded by the shrinking hood in a directed manner by blowing via at least one nozzle.

[0039] Furthermore, during shrinking, preferably during upper shrinking, at least one nozzle, preferably designed as a slot nozzle, can be directed toward the adjacent upper edge of the stack of goods. In this way, heat can be introduced in a targeted manner into the region of the heat shrink film that runs along the corresponding edge. For example, this allows for optimal welding of the edge region of a heat shrink seal to a cover film placed on the stack of goods.

[0040] During the contraction, preferably during the upper contraction, the air flow is directed via at least two oppositely disposed nozzles towards two oppositely disposed upper edges of the pile of goods. In this method, heat is applied simultaneously and in a targeted manner to two oppositely disposed edges of the pile of goods. These edges are preferably two longitudinal edges of the pile of goods. If the pile of goods is transported towards the device, for example, by means of a conveyor belt and is transported away from the device after contraction, the two longitudinal edges are oriented parallel to the transport direction of the pile of goods.

[0041] Advantageously, during the shrinking, preferably during the upper shrinking, at least one nozzle can be set in an oscillating motion about its horizontal axis. Such a movement is suitable, for example, when a shrink wrap is used as the shrink film. The oscillating motion can direct the air flow more evenly in the direction of the opposite edges of the edge on the upper side of the goods stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The following is an explanation of the embodiments of the present invention shown in the accompanying drawings.

[0043] Figure 1 shows an oblique view of an embodiment of the device according to the invention,

[0044] Figure 2 Shown according to Figure 1 a sectional view of an object, wherein the shrink frame and the shrink hood are in an upper position,

[0045] Figure 3 Shown according to Figure 2 object, wherein the shrink frame and the shrink hood are in a lower position,

[0046] Figure 4 A sectional view of another embodiment of the device according to the invention with a closed surface is shown, wherein the shrink frame and the shrink hood are in the upper position,

[0047] Figure 5 Shown according to Figure 4 object, wherein the shrink frame and the shrink hood are in a lower position,

[0048] Figure 6 A sectional view of another embodiment of the device according to the invention with a closed surface is shown, wherein the shrink frame and the shrink hood are in the upper position,

[0049] Figure 7 Shown according to Figure 6 object, wherein the shrink frame and the shrink hood are in a lower position,

[0050] Figure 8A sectional view of a further embodiment of the device according to the invention with a closed surface and a pivotable slot nozzle is shown, wherein the shrink frame and the shrink cap are in the upper position,

[0051] Fig. 9 A view showing the inside of the cover towards the shrink hood, and

[0052] Fig.10 The invention shows a method of using a slot nozzle with horizontally closer contact. Fig. 9 object.

[0053] Throughout the drawings, consistent reference symbols are used for the same or similar components. DETAILED DESCRIPTION

[0054] Figure 1 A device 1 is shown for shrinking a heat shrink film 3, not shown, placed around a pile of goods 2, also not shown. The device 1 comprises a frame 4 having a shrink frame 5 which can be moved in the vertical direction between an upper position and a lower position. The shrink frame 5 consists of four frame parts forming a quadrilateral recess 19.

[0055] A shrinking device (not shown in the figure) for shrinking the heat shrink film 3 by heating is provided at each frame part. The device 1 also includes a shrinking hood 6 that is open downward and forms a shrinking space above the shrinking frame 5. The shrinking hood 6 is constructed with a surrounding side wall 7 and a cover 8. In the embodiment shown, the shrinking hood 6 is connected to the shrinking frame 5 and thus forms a unit with the shrinking frame 5. When the shrinking frame 5 is vertically displaced, the shrinking hood 6 moves together. The device 1 also includes two blowers 9 that respectively generate air flows in the interior of the shrinking hood 6, and the blowers each have an impeller 20 driven by a drive 10. The impeller 20 of each blower 9 is located in the interior of the shrinking hood 6, and the corresponding drive 10 is arranged on the outside of the shrinking hood 6. In the embodiment shown, each impeller 20 is surrounded by a housing 21, wherein each housing 21 has a suction opening 22 on its lower side.

[0056] Figure 2 Shown according to Figure 1 The shrink hood 6 is connected to the shrink frame 5 in an airtight manner. The shrink frame 5 is in its upper position. The shrink frame 5 forms a recess 19 for the goods pile 2. The goods pile 2 has a lower side, by means of which the goods pile 2 rests on the pallet 23, four side faces and an upper side. In addition, the goods pile 2 has an edge 17 in the transition from each side face to the upper side.

[0057] Shrinking devices are arranged around the recess 19 , which in the illustrated embodiment each have at least one slot-like blowing nozzle 24 pointing obliquely downward for blowing heated air in order to shrink the heat shrink film 3 .

[0058] The frame 4 of the device 1, not shown, is located behind the shrink hood 6 or the goods pile 2 and is placed on the ground 15. The goods pile 2 with the heat shrink film 3 is shown centrally below the shrink hood 6. The housing 21 with the impeller 20 located therein is arranged on the inner side of the cover 8. An air guide section 11 is connected to each impeller 20, that is, to each housing 21. Each air guide section 11 has a nozzle 12 at its end opposite the impeller 20.

[0059] The air sucked from the shrinking space enclosed by the shrinking hood 6 by the impeller 20 via the corresponding suction openings 22 is directed back into the shrinking space enclosed by the shrinking hood 6 via the corresponding nozzles 12. In the position shown, the lower edge of the shrinking frame 5 is higher than the upper side of the goods stack 2. In this regard, in the depicted movement state, the shrinking process has not yet begun.

[0060] Figure 3 Shown according to Figure 2 In another motion state of the object, the lower edge of the shrink frame 5 is now located at the height of the pallet 23 below the cargo pile 2. The shrink frame 5 is displaced from its upper position to its lower position accordingly. The heated air blown out via the blow-out nozzle 24 shrinks the heat shrink film 3 in the interior of the shrink hood 6. At the same time, the blower 9 draws air from the upper region of the shrink space in the interior of the shrink hood 6 in the direction of the arrow 25. Immediately thereafter, the sucked air is directed through the corresponding air guide section 11 again via the nozzle 12 in the direction of the arrow 26 into the shrink space surrounded by the shrink hood 6. In the illustrated embodiment, each of the two nozzles 12 is constructed as a slot nozzle. The orientation of the slot nozzle is such that in the lower position of the shrink frame 5, the blown air is blown onto the adjacent edge 17 of the cargo pile 2 in the direction of the arrow 26.

[0061] As from Figure 3 It can be seen that in the lower position of the shrink frame 5 the distance A between the upper side of the goods stack 2 and the cover 8 of the shrink hood 6 is at least 300 mm.

[0062] Figure 4 FIG. 2 shows a cross-sectional view of another embodiment of a device 1 according to the present invention. Figure 2The device 1 shown in FIG. 1 differs only in that it has a closing surface 13, which is adapted in its contour and its dimensions to the contour and dimensions of the recess 19 of the shrink frame 5. The closing surface 13 on the one hand and the shrink frame 5 and the shrink hood 6 on the other hand can be moved relative to each other. The shrink frame 5 forms the recess 19 for the stack of goods 2 and is in its upper position. The closing surface 13 is located in the recess 19 of the shrink frame 5 and is arranged in such a way that the closing surface 13 approaches the cover 8 of the shrink hood 6 as the shrink frame 5 is gradually displaced into its lower position.

[0063] The closing surface 13 has a foot 14 and rests on the ground 15 at the bottom with the foot. The closing surface 13 is adapted to the recess 19 in terms of its contour and size so that a gap remains between the outer edge of the closing surface 13 and the inner edge of the recess 19. The closing surface 13 reduces heat losses when the shrink frame 5 is in its upper position. In addition, the closing surface 13 is arranged at such a height that it lies on the goods stack 2 on the one hand and substantially closes the shrink frame 5 at its bottom on the other hand. In this regard, the recess 19 of the shrink frame 5 and thus the shrink space of the shrink hood 6 can be almost closed by the closing surface 13 except in the region of the above-mentioned gap.

[0064] exist Figure 5 In the embodiment shown, the lower edge of the shrink frame 5 is now arranged lower than the lower side of the goods pile 2. The shrink frame 5 is displaced from its upper position to its lower position accordingly. The air heated by the shrinking device shrinks the heat shrink film 3 in the interior of the shrink hood 6. The two blowers 9 again suck air from the upper region of the shrink space in the interior of the shrink hood 6 in the direction of the arrow 25, and guide the air to the nozzle 12 via the correspondingly connected air guide section 11. Via the nozzle 12, the hot air is directed again in the direction of the arrow 26 into the shrink space surrounded by the shrink hood 6. In the embodiment shown, each of the two nozzles 12 is configured as a slot nozzle. The orientation of the slot nozzle is such that in the lower position of the shrink frame 5, the blown air is blown onto the adjacent edge 17 of the goods pile 2 in the direction of the arrow 26. By lowering the shrink frame 5 and therefore also the shrink hood 6, the closing surface 13 is displaced into the interior of the shrink hood 6. The foot 14 does not hinder the air flow directed by the nozzle 12 , since it is arranged in such a way that it does not partially cover the corresponding slot nozzle.

[0065] Figure 6 FIG. 2 shows a cross-sectional view of another embodiment of a device 1 according to the present invention. Figure 4The device 1 shown in FIG. 1 differs only in that the closing surface 13 is now suspended from a rod 16, wherein the rod 16 is guided through the cover 8 of the shrink hood 6 and is fastened to the frame 4. The frame 4 is placed on the ground 15. The closing surface 13 on the one hand and the shrink frame 5 and the shrink hood 6 on the other hand can be moved relative to each other. The shrink frame 5 forms a recess 19 for the stack of goods 2 and is in its upper position. The closing surface 13 is located in the recess 19 of the shrink frame 5 and is arranged in such a way that the closing surface 13 approaches the cover 8 of the shrink hood 6 as the shrink frame 5 is gradually displaced into its lower position.

[0066] Figure 7 The position in which the lower edge of the shrink frame 5 is arranged lower than the lower side of the cargo pile 2 is shown. The shrink frame 5 is displaced from its upper position to its lower position accordingly. This is again the beginning of the shrinking process, in which the shrink frame 5 is displaced vertically upward. The air heated by the shrinking device shrinks the heat shrink film 3 in the interior of the shrinking hood 6. The blower 9 draws air from the upper region of the shrinking space in the interior of the shrinking hood 6 in the direction of the arrow 25, and guides the air to the nozzle 12 via the corresponding connected air guide section 11. Via the corresponding nozzle 12, the hot air is directed again in the direction of the arrow 26 into the shrinking space surrounded by the shrinking hood 6. In the illustrated embodiment, each of the two nozzles 12 is configured as a slot nozzle. The orientation of the slot nozzle is such that in the lower position of the shrink frame 5, the blown air is blown onto the adjacent edge 17 of the cargo pile 2 in the direction of the arrow 26.

[0067] Figure 8 A cross-sectional view of another embodiment of the device 1 according to the present invention is shown. Figure 4 The device 1 of FIG. 1 differs only in that the nozzles 12 are arranged pivotably about a horizontal axis 18. Each nozzle 12 can be pivoted, for example, by means of an electric motor (not shown). The pivoting of each nozzle 12 enables a precise orientation of each nozzle 12 at the corresponding edge 17 of the stack 2 of goods. This adaptation can also be carried out during the vertical displacement of the retraction frame 5. Thus, the edges 17 of stacks 2 of goods of different heights can also be optimally retracted.

[0068] Fig. 9 The view of the underside of the cover 8 facing the shrink hood 6 is shown. Each of the two impellers 20 is surrounded by a housing 21, wherein each housing 21 has a suction opening 22 on its underside. An air guide section 11 is connected to each impeller 20, that is, to each housing 21. Each air guide section 11 has a nozzle 12 at its end opposite the impeller 20. Each nozzle 12 is designed as a slot nozzle.

[0069] exist Fig. 9In the embodiment, the distance between the two nozzles 12 is greater than that in Fig.10 This is because the two nozzles 12 that can be moved horizontally in the direction of arrow 27 are Fig.10 In order to realize such a displacement of the nozzle 12, the length of each air guide section 11 can be changed according to the corresponding position of the corresponding nozzle 12. In this way, each air guide section 11 can be constructed to be telescopic, for example. Therefore, although the position of the impeller 20 is fixed, the corresponding nozzle 12 can still be moved horizontally in the direction of the arrow 27. Therefore, each nozzle 12 can be optimally positioned, for example, relative to the corresponding edge 17. In addition, it is also possible that each nozzle 12 can also pivot around a horizontal axis.

[0070] Alternatively, in the case of the blower 9 , the complete assembly consisting of the impeller 20 , the housing 21 surrounding the impeller 20 , the air guiding section 11 and the nozzle 12 can also be arranged as a whole so as to be horizontally displaceable in the direction of the arrow 27 .

Claims

1. A device (1) for shrinking a heat shrink film (3) placed around a preferably palletized pile of goods (2), comprising a shrink frame (5) movable in the vertical direction between an upper position and a lower position on a frame (4), forming a recess (19) for the pile of goods (2), at least one shrinking device for shrinking the heat shrink film (3) by heating is arranged on the shrink frame, wherein: The device (1) comprises a shrinking hood (6) which is open downward and forms a shrinking space above the shrinking frame (5), the shrinking hood comprising a surrounding side wall (7) and a cover (8), wherein the shrinking hood (6) is movable in the vertical direction, and wherein the device (1) also comprises at least one blower (9) which generates an air flow in the interior of the shrinking hood (6), wherein at least one blower (9) comprises an impeller (20) driven by a drive (10), characterized in that at least one air guide section (11) is connected to the impeller of at least one blower (9), and the air guide section has at least one nozzle (12) at its end opposite to the impeller (20), so that the air sucked in by the impeller (20) in the shrinking space enclosed by the shrinking hood (6) can be directed back into the shrinking space enclosed by the shrinking hood (6) via the at least one nozzle (12).

2. Device (1) according to the preceding claim, characterized in that At least one nozzle (12) is designed as a slot nozzle.

3. The device (1) according to any one of the preceding claims, characterized in that At least one blower (9) is designed as a radial blower.

4. Device (1) according to any one of the preceding claims, characterized in that An impeller (20) of at least one blower (9) and an air guide section (11) extending from the impeller (20) are fastened below the cover (8) of the shrink hood (6) and either indirectly or directly to the inner side of the cover (8) of the shrink hood (6).

5. Device (1) according to any one of the preceding claims, characterized in that At least one heating element for heating the air flowing through the air guide section (11) is arranged in at least one air guide section (11).

6. Device (1) according to any one of the preceding claims, characterized in that In at least one blower (9), the assembly consisting of the impeller (20), the air guide section (11) and the at least one nozzle (12) is designed to be horizontally displaceable.

7. Device (1) according to any one of the preceding claims, characterized in that In at least one blower (9), the at least one nozzle (12) is designed to be horizontally displaceable, and the length of the air guide section (11) is variable depending on the respective position of the at least one nozzle (12).

8. Device (1) according to any one of the preceding claims, characterized in that In at least one blower (9), at least one nozzle (12) is vertically movable.

9. Device (1) according to any one of the preceding claims, characterized in that In at least one blower (9), at least one nozzle (12) is arranged pivotably about a horizontal axis (18).

10. Device (1) according to any one of the preceding claims, characterized in that The device (1) has a closing surface (13), which is adapted in its contour and its dimensions to the contour and dimensions of the recess (19) of the shrink frame (5) so that on the one hand the closing surface (13) and on the other hand the shrink frame (5) and the shrink hood (6) can move relative to each other, wherein, when the shrink frame (5) is in its upper position, the closing surface (13) is preferably arranged in a fixed position in the recess (19) so that the closing surface (13) approaches the cover (8) of the shrink hood (6) as the shrink frame (5) is gradually displaced into its lower position.

11. Device (1) according to any one of the preceding claims, characterized in that The height of the shrinkage space is at least 300 mm higher than the height of the pile (2) of goods to be packaged.

12. Device (1) according to any one of the preceding claims, characterized in that The shrink hood (6) is preferably connected to the shrink frame (5) in an airtight manner.

13. Device (1) according to any of the preceding claims, characterized in that In at least one blower (9), the impeller (20) is surrounded by a housing (21) having a suction opening (22), wherein at least one ventilation section (11) is connected to the housing (21).

14. A method for shrinking a heat shrink film (3) placed around a preferably palletized pile of goods (2), preferably using a device (1) having a shrink frame (5) movable in the vertical direction between an upper position and a lower position on a frame (4) and forming a recess (19) for the pile of goods (2), at least one shrinking device for shrinking the heat shrink film (3) by heating is arranged on the shrink frame, wherein: The device (1) comprises a shrinking hood (6) which is open downward and forms a shrinking space above the shrinking frame (5), the shrinking hood comprising a surrounding side wall (7) and a cover (8), wherein the shrinking hood (6) moves in a vertical direction, and wherein the device (1) also comprises at least one blower (9) which generates an air flow in the interior of the shrinking hood (6), wherein at least one blower (9) comprises an impeller (20) driven by a drive (10), particularly preferably when using the device (1) according to any of the preceding claims, characterized in that at least one air guide section (11) is connected to the impeller (20) of at least one blower (9), the air guide section having at least one nozzle (12) at its end opposite to the impeller (20), so that the air sucked in by the impeller (20) in the shrinking space enclosed by the shrinking hood (6) is directed back into the shrinking space enclosed by the shrinking hood (6) via the at least one nozzle (12).

15. The method according to the preceding claim, characterized in that The air sucked in by the impeller (20) in the contraction space surrounded by the contraction hood (6) is directed back into the contraction space surrounded by the contraction hood (6) via at least one nozzle (12) designed as a slot nozzle.

16. The method according to any one of the two preceding claims, characterized in that In at least one blower (9), the assembly consisting of the impeller (20), the air guide section (11) and the at least one nozzle (12) is moved horizontally.

17. The method according to any one of claims 14 to 16, characterized in that In at least one blower (9), the at least one nozzle (12) is horizontally movable, and the length of the air guide section (11) varies depending on the respective position of the at least one nozzle (12).

18. The method according to any one of claims 14 to 17, characterized in that In at least one blower (9), at least one nozzle (12) is moved vertically.

19. The method according to any one of claims 14 to 18, characterized in that In at least one blower (9), at least one nozzle (12) is pivotable about a horizontal axis (18).

20. The method according to any one of claims 14 to 19, characterized in that At least one heating element is arranged in at least one air guide section (11), and the at least one heating element heats the air flowing through the air guide section (11).

21. The method according to any one of claims 14 to 20, characterized in that The device (1) has a closing surface (13), which is adapted in its contour and its dimensions to the contour and dimensions of the recess (19) of the shrink frame (5) in such a way that on the one hand the closing surface (13) and on the other hand the shrink frame (5) and the shrink hood (6) move relative to each other, wherein, when the shrink frame (5) is in its upper position, the closing surface (13) is preferably arranged in a fixed position in the recess (19) so that the closing surface (13) approaches the cover (8) of the shrink hood (6) as the shrink frame (5) is gradually displaced into its lower position.

22. The method according to any one of claims 14 to 21, characterized in that In the lower position of the shrink frame (5), the distance A between the upper side of the stack of goods (2) and the cover (8) of the shrink hood (6) is at least 300 mm.

23. The method according to any one of claims 14 to 22, characterized in that During the retraction, preferably during the upper retraction, at least one nozzle (12) is directed towards an adjacent upper edge (17) of the stack (2).

24. The method according to any one of claims 14 to 23, characterized in that During the contraction, preferably during the upper contraction, an air flow is directed via at least two oppositely disposed nozzles (12) towards two oppositely disposed upper edges (17) of the stack of goods (2).

25. The method according to any one of claims 14 to 24, characterized in that During the retraction, preferably during the upper retraction, at least one nozzle (12) is set in an oscillating movement about its horizontal axis (18).

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