Process and apparatus for wrapping a stack of goods in film

Abstract

A process for wrapping a stack of goods in film, wherein a portion of film is drawn from a film supply, cut, opened by a film opening means and pulled over the stack of goods by a travelling pulling means, wherein, after being drawn off and cut, the portion of film is transported lengthwise by a film transport means to the film opening means, characterized in that the portion of film is transported from the cutting unit as far as the film opening means by being gripped by frictional engagement between at least two conveyor members pressed together and circulating endlessly in a transport direction.

Claims

1. An apparatus for wrapping a stack of goods in a film, with a film supply, a film take-off apparatus for drawing off a portion of film, a cutting means for cutting the portion of film off the film supply, a film opening means for gripping and opening the portion of film, and a pulling means that is movable between an initial sheathing height (H) and a final sheathing height (h), wherein a film transport means is disposed between the cutting means and the film opening means, said film transport means being configured to transport the cut-off portion of film lengthwise to the film opening means, wherein the film transport means comprises a first endlessly circulating conveyor member and a second endlessly circulating conveyor member pressed against the first conveyor member, both of which can be driven in a transport direction and between which the portion of film is receivable by frictional engagement from the cutting means as far as the film opening means, wherein the film transport means, with the film received in the frictional engagement between the first endlessly circulating conveyor member and the second endlessly circulating conveyor member, transports the film from below the final sheathing height (h) to at least the initial sheathing height (H).

2. The apparatus as claimed in claim 1, wherein a welding means is arranged below the initial sheathing height (H) to form a film shroud which is closed on one side.

3. The apparatus as claimed in claim 2, wherein the film take-off apparatus and/or the cutting means and/or the welding means is/are disposed within a film preparation region (V), which extends from below the final sheathing height (h) to 75% of the initial sheathing height (H).

4. The apparatus as claimed in claim 2, wherein the film take-off apparatus and/or the cutting means and/or the welding means is/are disposed at a height of no more than 2 m above a workshop level on which the apparatus is located.

5. The apparatus as claimed in claim 1, wherein the film supply, the film take-off apparatus and the cutting means are disposed in a first region of a multistorey unit, and the stack of goods to be wrapped and the film-opening and pulling means are disposed in a second region located above or below the first region.

6. The apparatus as claimed in claim 1, wherein the first conveyor member comprises two or more first conveyor part-members.

7. The apparatus as claimed in claim 1, wherein the second conveyor member comprises two or more second conveyor part-members.

8. The apparatus as claimed in claim 1, wherein the film transport means has an entry region, a vertical conveying region which extends up to or above the initial sheathing height (H), and a transfer region adjoining it, which extends to above the pulling means.

9. The apparatus as claimed in claim 1, wherein the transfer region comprises at its end a delivery region within which a portion of the film is transferred vertically downwards.

10. The apparatus as claimed in claim 1, wherein the film transport means is configured to transport the portion of film up to a film transfer height, which is located a handling distance above the initial sheathing height (H), wherein the handling distance corresponds to at least a height of the portion of film on the pulling means.

11. The apparatus as claimed in claim 1, wherein the film transport means is configured as a film storage unit, in which a predetermined length of film and/or a plurality of cut-off portions of film can be stored.

12. An apparatus for wrapping a stack of goods in a film, with a film supply, a film take-off apparatus for drawing off a portion of film, a cutting means for cutting the portion of film off the film supply, a film opening means for gripping and opening the portion of film, and a pulling means that is movable between an initial sheathing height (H) and a final sheathing height (h), wherein a film transport means is disposed between the cutting means and the film opening means, said film transport means being configured to transport the cut-off portion of film lengthwise to the film opening means, wherein the film transport means comprises a first endlessly circulating conveyor member and a second endlessly circulating conveyor member pressed against the first conveyor member, both of which can be driven in a transport direction and between which the portion of film is receivable by frictional engagement from the cutting means as far as the film opening means, wherein the first endlessly circulating conveyor member and the second endlessly circulating conveyor member, pressed together with the portion of film between, run continuously between the cutting means from below the final sheathing height (h) to the film opening means at or above the initial sheathing height (H).

13. An apparatus for wrapping a stack of goods in a film, with a film supply, a film take-off apparatus for drawing off a portion of film, a cutting means for cutting the portion of film off the film supply, a film opening means for gripping and opening the portion of film, and a pulling means that is movable between an initial sheathing height (H) and a final sheathing height (h), wherein a film transport means is disposed between the cutting means and the film opening means, said film transport means being configured to transport the cut-off portion of film lengthwise to the film opening means, wherein the film transport means comprises a first endlessly circulating conveyor member and a second endlessly circulating conveyor member pressed against the first conveyor member, both of which can be driven in a transport direction and between which the portion of film is receivable by frictional engagement from the cutting means as far as the film opening means, wherein the first endlessly circulating conveyor member and the second endlessly circulating conveyor member connect from below the final sheathing height (h) to at least the initial sheathing height (H).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be explained by describing a worked embodiment, reference being made to a drawing, in which

(2) FIG. 1 shows a perspective view of an apparatus in accordance with the invention,

(3) FIG. 2 shows a schematic side view of the apparatus of FIG. 1,

(4) FIG. 3 shows an enlarged excerpt from FIG. 1, and

(5) FIG. 4 shows an embodiment in a variant with two conveyor part-members.

DETAILED DESCRIPTION

(6) The illustrations show an apparatus which is known in principle for pulling a stack of goods 2 into a wrapping film 4, which nowadays is usually a stretch film, in contrast to the shrink film which was generally used in the past, and which had to be placed on the stack of goods with the application of heat.

(7) The apparatus has a mount, which is not illustrated in detail, for holding a roll of film 6, which forms a store of wrapping film 4, wherein the film is often wound up in the form of a gusseted tubular film.

(8) A return roller 8 and a pair of feed rollers 10 are illustrated as examples of a film take-off apparatus which can be controlled in order to draw off a portion of film of predetermined length. Seen in the unwinding direction 5 of the wrapping film 4, a cutting means 12 is provided beneath the film take-off apparatus 8, 10, with a knife arranged transversely to the film and a welding means 14 with welding bars 14a, b arranged on both sides of the film.

(9) Beneath the cutting and welding means 12, 14 there is an entry region 18, pointing vertically downwards, of a film transport means 20, which works in a transport direction 21 and consists substantially of two conveyor members in the form of conveyor belts 22, 24, which are at least in parts pressed together within a conveying region which begins with the entry region 18 and ends with a delivery region 26. The film transport means transports, lengthwise, the cut portion of film, which is welded on one side, wherein a longitudinal direction of the portion of film is the same as the transport direction 21.

(10) FIG. 4 shows schematically that the film transport means can consist not only of two conveyor members, but that each conveyor member may be formed from two or more conveyor part-members, which complement one another. It is for example possible, as shown in FIG. 4, for a first conveyor member to consist of two first conveyor part-members 22.1, 22.2, which may, for example, be configured as conveyor belts or part conveyor belts and face a unitary second conveyor member 24 in the form of a conveyor belt, wherein a portion of film 7 is received by frictional engagement between the conveyor members or conveyor part-members when they are pressed together. The conveyor members or conveyor part-members need not necessarily be conveyor belts, but rather rollers, grippers or suction elements under a partial vacuum, suction belts or the like may also be used.

(11) In the embodiment illustrated, the entry region 18 is first followed by a horizontal conveying region 28, in which the conveyor belts 22, 24 run substantially horizontally. Adjoining the horizontal conveying region 28 is a conveying region 30 running vertically upwards, in the course of which the adjacent conveyor belts 22, 24 are deflected more than once around horizontal return rollers 32 in alternating directions deviating slightly from the vertical, so that the conveyor belts 22, 24 are as far as possible pressed together over a great part of or the entire length of the vertical conveying region 30.

(12) Adjoining the vertical conveying region 30 is a horizontal transfer region 34, which ends with the delivery region 26 pointing vertically downwards inside a hoist frame 36 of the apparatus. The delivery region 26 is located above a film opening means 40, which includes means for gripping and opening the film.

(13) Beneath the film opening means 40, which is joined firmly to the hoist frame 36, there is a pulling means 42 which travels vertically and which, in the embodiment illustrated, has four reefing hoops 44 arranged in the corners of a square or rectangle to take up and reef a portion of film. The pulling means 42 can travel vertically between an initial sheathing height H illustrated in FIGS. 1 and 2 up to a final sheathing height h, in order to pull a cut portion of film over the stack of goods 2.

(14) The initial sheathing height H is dimensioned such that a stack of goods 2 with the greatest possible height can be processed by the apparatus with no difficulty, while the final sheathing height h is just below a bottom edge 2a of a stack 2, so that if needed, the film can be pulled over the stack with an “understretch”, reaching beneath the bottom edge 2a.

(15) The stack of goods 2 itself is located on a conveying means 48 spaced a vertical distance F above a workshop level 50 on which the apparatus is arranged and from where work can be carried out on the apparatus, such as maintenance or repair work and replacing the roll of film 6.

(16) In order for work to be carried out on the feed rollers 10, the cutting means 12 and the welding means 14 and for the roll of film 6 to be replaced in a simple manner, e.g. by an operator standing on the workshop level 50, the apparatus elements mentioned should not be located higher than for example 1.5 m above the workshop level 50, so that it can be accessed with no difficulty. The roll of film 6 may be arranged higher, such as up to 2 m or even higher, because it is not usually moved by an operator directly, but rather by means of a transport device, such as a fork-lift truck.

(17) Irrespective of whether a workshop level 50 is available as the “reference level” for favourable positioning of the take-off apparatus and cutting and welding means, substantial benefits are available if the equipment referred to is located below the initial sheathing height H, namely expeditiously within a film preparation region V, which extends from below the final sheathing height h to no more than 50% or 75% of the initial sheathing height H.

LIST OF REFERENCE NUMERALS

(18) 2 stack of goods 2a bottom edge 4 film 4a lower film edge 5 unwinding direction 6 roll of film (film supply) 7 portion of film 8 return roller 10 feed rollers 12 cutting means 14 welding means 14a, b welding bar 18 entry region 20 film transport means 21 transport direction 22 first conveyor belt (conveyor member) 22.1, 22.2 first part conveyor belt (conveyor part-member) 24 second conveyor belt (conveyor member) 26 delivery region 28 horizontal conveying region 30 vertical conveying region 32 return rollers 34 transfer region 36 hoist frame 40 film opening means 42 pulling means 44 reefing hoop 48 conveying means 50 workshop level H initial sheathing height h final sheathing height F distance between 48 and 50 V film preparation region