METHOD AND APPARATUS FOR TRANSFERRING A FILM WOUND ONTO A WINDING MANDREL, ORIENTED IN PARTICULAR VERTICALLY AND PREFERABLY SUPPORTED EXCLUSIVELY IN THE REGION OF ITS UPPER END

Abstract

A method is disclosed for transferring a film, preferably a wound-on stretch film, wound onto a winding mandrel, oriented in particular vertically and preferably supported exclusively in the region of its upper end, of an unwrapping apparatus, such that when the transfer position of the winding mandrel is reached, the film wound onto the winding mandrel is pulled off the winding mandrel by means of at least one transfer device and delivered to a disposal area. An apparatus for transferring a film, preferably a wound-on stretch film, wound onto a winding mandrel, oriented in particular vertically and preferably supported exclusively in the region of its upper end, of an unwrapping apparatus, is disclosed. The apparatus encompasses at least one transfer device for pulling off the film wound onto the winding mandrel when the transfer position of the winding mandrel is reached.

Claims

1. A method for transferring a film (3), preferably a wound-on stretch film, wound onto a winding mandrel (5), oriented in particular vertically and preferably supported exclusively in the region of its upper end, of an unwrapping apparatus, such that when the transfer position of the winding mandrel (5) is reached, the film (3) wound onto the winding mandrel (5) is pulled off the winding mandrel (5) by means of at least one transfer device (7) and delivered to a disposal area.

2. The method according to claim 1, wherein the winding mandrel (5) on the one hand, and at least a sub-region of the transfer device (7), preferably the entire transfer device (7), on the other hand, are displaceable relative to one another in a horizontal direction and/or in a vertical direction.

3. The method according to claim 1, wherein at least a sub-region of the transfer device (7), preferably the entire transfer device (7), is horizontally and/or vertically displaceable.

4. The method according to claim 1, wherein the film (3) wound onto the winding mandrel (5) protrudes at the bottom with respect to the lower end of the winding mandrel (5), forming a fringe (11).

5. The method according to claim 2, wherein a displacement of the winding mandrel (5) and/or a displacement at least of a sub-region of the transfer device (7), preferably of the entire transfer device (7), occurs without contact between the fringe (11) and the transfer device (7).

6. The method according to claim 1, wherein in the transfer position, the lower end of the winding mandrel (5) is arranged above the transfer device (7).

7. The method according to claim 1, wherein at least one transfer device (7) encompasses at least one drivable roller (8) that interacts with the adjacent sub-region of the winding mandrel (5) in order to pull off the film (3).

8. The method according to claim 1, wherein at least one transfer device (7) encompasses at least two rollers (8) that form a gap between them and preferably are displaceable with respect to one another in order to modify the width of the gap, at least one of the two rollers (8) being driven by a drive system.

9. The method according to claim 1, wherein in order to convey the film (3) to the disposal area, an aspiration system (13) encompassing a suction opening is used for further transport of the film (3) that is in the process of being pulled off.

10. An apparatus for transferring a film (3), preferably a wound-on stretch film, wound onto a winding mandrel (5), oriented in particular vertically and preferably supported exclusively in the region of its upper end, of an unwrapping apparatus, in particular for carrying out the method according to one of the preceding claims, the apparatus encompassing at least one transfer device (7) for pulling off the film (3) wound onto the winding mandrel (5) when the transfer position of the winding mandrel (5) is reached.

11. The apparatus according to claim 10, wherein the winding mandrel (5) on the one hand, and at least a sub-region of the transfer device (7), preferably the entire transfer device (7), on the other hand, are arranged displaceably relative to one another in a horizontal direction and/or in a vertical direction.

12. The apparatus according to claim 10, wherein at least a sub-region of the transfer device (7), preferably the entire transfer device (7), is arranged horizontally and/or vertically displaceably.

13. The apparatus according to claim 10, wherein at least one transfer device (7) encompasses at least one drivable roller (8) that interacts with the adjacent sub-region of the winding mandrel (5) in order to pull off the film (3).

14. The apparatus according to claim 10, wherein at least one transfer device (7) encompasses at least two rollers (8) that form a gap between them and preferably are displaceable with respect to one another in order to modify the width of the gap, at least one of the two rollers (8) being driven by a drive system.

15. The apparatus according to claim 14, wherein the two rollers (8) that form a gap between them, and are closest to the, preferably lower, end of the winding mandrel (5), are oriented horizontally.

16. The apparatus according to claim 14, wherein the two rollers (8) that form a gap between them, and are closest to that end of the winding mandrel (5) over which the film (3) is to be pulled off, are arranged in alignment with that end of the winding mandrel (5) over which the film (3) is to be pulled off.

17. The apparatus according to claim 13, wherein at least a sub-region of the surface of at least one drivable roller (8) comprises a friction-increasing surface, for example a rubber coating.

18. The apparatus according to claim 10, wherein in order to convey the film (3) to the disposal area, the apparatus comprises an aspiration system (13) encompassing a suction opening for further transport of the film (3) that is in the process of being pulled off.

19. The apparatus according to claim 10, wherein the suction opening is arranged in alignment with that end of the winding mandrel (5) over which the film (3) is to be pulled off.

20. The apparatus according to claim 10, wherein a delivery device, in particular a delivery device embodied as a funnel, is provided in order to deliver the pulled-off film (3) to the disposal area.

21. The apparatus according to claim 10, wherein the apparatus comprises, in the region in which the winding mandrel (5) is located in its transfer position, a detection device that activates the transfer device upon detection of a winding mandrel (5) having a film (3) wound thereunto.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The invention will be explained below with reference to the drawings, in which:

[0028] FIGS. 1 to 5 are side views of a first exemplifying embodiment of an apparatus according to the present invention and of a method according to the present invention, at different points in time;

[0029] FIG. 6 is a side view of a second exemplifying embodiment of an apparatus according to the present invention;

[0030] FIGS. 7 to 11 are top views corresponding to the side views of FIGS. 1 to 5; and

[0031] FIG. 12 is a top view corresponding to the side view of FIG. 6.

[0032] In all the Figures, matching reference characters are used for identical or similar components.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

[0033] A goods stack 1 is, as a rule, arranged on a pallet 2 and is secured with a film 3. Such a film 3 can be, for example, a shrink-wrap film, a stretch film, a stretch hood film, or a stretch wrap film. A goods stack 1 packaged with such a film 3 is unwrapped using an unwrapping apparatus, for subsequent removal of the individual goods of goods stack 1.

[0034] An unwrapping apparatus comprises a frame 4 having a winding mandrel 5. Winding mandrel 5 is movable in all directions in a horizontal direction by way of a configuration that is not depicted in further detail. Winding mandrel 5 can thereby be guided externally around goods stack 1 along the side edges for the purpose of unwrapping.

[0035] Winding mandrel 5 can be rotated around its own longitudinal axis by means of a drive system (not depicted), and is supported in the region of its upper end and is oriented vertically. The lower end of winding mandrel 5 is freely suspended. Winding mandrel 5 is usually split in two when viewed in its longitudinal dimension, and is made up of a stationary bar and a bar that is pivotable with respect to the stationary bar,

[0036] An unwrapping apparatus furthermore usually comprises an aspiration device (not depicted in further detail) and a cutting device (not depicted in further detail). For unwrapping purposes, the aspiration device is moved against goods stack 1, the aspiration device being aspirated into place against film 3. The aspiration device is then moved via a cylinder toward winding mandrel 5. As a result, the aspirated film 3 is pulled against the cutting device and film 3 is thereby cut through vertically. If film 3 also comprises an underlayer, that is also cut through vertically,

[0037] The free vertical edge of film 3 is then introduced into the interstice between the stationary bar and the pivotable bar. Once the pivotable bar is swung in, the corresponding edge of film 3 is clamped in between the stationary bar and the pivotable bar. Winding mandrel 5 then rotates around its longitudinal axis and is moved simultaneously around goods stack 1 so that film 3 is thereby wound on. If film 3 also comprises an underlayer, film 3 is wound on in that region as well.

[0038] The speed at which winding mandrel 5 is guided around the rectangular goods stack 1, and the rotation speed of winding mandrel 5, are coordinated with the contour of goods stack 1 so that film 3 is uniformly wound on upon unwrapping. During unwrapping of the first two side surfaces film 3 can be immobilized, for example by means of PTFE clamping pieces, centeredly on that side surface of goods stack 1 which is located oppositely from the cut side. In supplementary fashion, film 3 can also be held by means of PTFE clamping pieces at the fourth corner, i.e. the last corner of goods stack 1 that is unwrapped, until shortly before the end of the unwrapping process.

[0039] As is evident from the Figures, the unwrapping apparatus encompasses a conveyor 6 on which goods stack 1 to be unpacked is transported into frame 4. Arranged in the region of the unwrapping apparatus in conveyor 6 is a lifting system 6 in order to allow goods stack 1 to be raised for unwrapping purposes. Arranged next to conveyor 6 is a transfer device 7 that comprises, in the exemplifying embodiment depicted, two rollers 8 that form a gap between them. Rollers 8 are displaceable with respect to one another by means of a drive system (not depicted) in order to modify the width of the gap. At least one of the two rollers 8 is drivable by means of a drive system (not depicted). In FIG. 1, the two rollers 8 are at a greater distance from one another so that the gap is wide. Winding mandrel 5 has not yet been moved against goods stack 1, enveloped by film 3, for unwrapping. Winding mandrel 5 is instead in the transfer position, so that the lower end of winding mandrel 5, over which film 3 will later be pulled off, is in alignment with the transfer device, i.e. with the gap formed by the two rollers 8.

[0040] Upon unwrapping, a holddown 9 is usually lowered onto the upper side of goods stack 1 in order to stabilize goods stack 1 during unpacking; this is helpful in particular with products that shift easily, and is visible in FIG. 2. A cylinder 10 is provided in order to raise and lower holddown 9. If film 3 is embodied as a hood, holddown 9 is equipped on its lower side with heating wires 9 arranged in a star shape. Film 3 is cut through in the region of the upper side along heating wires 9.

[0041] In FIG. 2, holddown 9 is resting on the upper side of goods stack 1, and winding mandrel 5 has already unwrapped approximately half of goods stack 1. In the exemplifying embodiment depicted, winding mandrel 5 is oriented with respect to film 3 in such a way that film 3 wound onto winding mandrel 5 protrudes at the bottom with respect to the lower end of winding mandrel 5, forming a fringe 11.

[0042] Once winding mandrel 5 has pulled film 3 completely off, winding mandrel 5 is displaced horizontally into its transfer position, this being depicted in FIG. 3. A carriage (not depicted in further detail) is provided for this displacement in the region of the upper end of winding mandrel 5. Fringe 11 does not come into contact with any component, and also not with transfer device 7, in the context of this displacement. Fringe 11 thus cannot fold over.

[0043] Transfer device 7 is then raised vertically, this being depicted in FIG. 4. Having thus been raised, fringe 11 ends up in the gap between the two rollers 8 and thus in the access region of rollers 8. The clamping connection is released, by displacement of the displaceable bar, before film 3 is pulled off.

[0044] Rollers 8 are then moved toward one another so that the gap becomes smaller and fringe 11 becomes clamped between rollers 8. After clamping, at least one of the two rollers 8 is caused to move by means of a drive system (not depicted in further detail) so that film 3 is pulled downward off winding mandrel 5. In the exemplifying embodiment depicted, for example as is apparent from FIG. 7, in the position in which the gap is largest each roller 8 is covered at the top by a respective panel 12, panels 12 being arranged so that they form a funnel directed toward the gap.

[0045] In the embodiment according to FIG. 5, an aspiration system 13, encompassing a suction opening, is provided for further transport of film 3 that is in the process of being pulled off. A conduit 14 is connected to the suction opening. A negative pressure is generated in conduit 14 by means of a blower (not depicted in further detail), so that the pulled-off film is aspirated and can thereby be further transported in conduit 14.

[0046] FIG. 6 shows an exemplifying embodiment in which the pulled-off film 3 is automatically delivered to a disposal area, which in the exemplifying embodiment depicted is embodied as a container 15.

[0047] FIGS. 7 to 12 depict plan views corresponding to the side views of FIGS. 1 to 6. Because FIGS. 3 and 4 differ only in that in FIG. 4 transfer device 7 has already been moved upward, FIGS. 9 and 10 are identical.