WO1992007761A1

WO1992007761A1 - Method of palletization and device for carrying it out

Info

Publication number: WO1992007761A1
Application number: PCT/FR1991/000842
Authority: WO
Inventors: Patrick Gennesson
Original assignee: Patrick Gennesson
Priority date: 1990-10-29
Filing date: 1991-10-25
Publication date: 1992-05-14
Also published as: AU8873991A; EP0507920A1; DE69106344T2; CA2072593A1; FR2668448B1; DE69106344D1; FR2668448A1; EP0507920B1; ES2069314T3

Abstract

The method is uncommon in that it comprises: at least one reel (1) for receiving the film (F), means (2) capable of cutting the film (F) into at least two widths (F1), means (3) capable of transforming the widths (F1) in order to increase their strength, means capable of displacing the reel (1) and all the cutting (2) and transforming (3) means according to the height of the items to be palletized, equipment for temporarily retracting the cutting means (2).

Description

PALLETIZING PROCESS AND IMPLEMENTATION DEVICE.

The invention relates to the technical sector of packaging materials.

The problem that the invention proposes to solve is to be able to attach and hold in position various goods, objects and products on pallets. More particularly, but not limited to, the problem posed applies to products which are held by means of a plastic film, in particular a plastic film of the stretchable type, known to have elastic stretching and self-adhesive capacities.

This stretch film can be wrapped around the products according to two modes of packaging, either manually or, most frequently, automatically, using a palletizing machine of all known types and appropriate.

According to a first mode of packaging, the film is wound over its entire width. In this case, after winding, no gap appears, so that the products cannot breathe. This can result in a condensation phenomenon capable of generating significant disadvantages for foodstuffs, for example.

According to a second mode of packaging, the film is previously cut into widths of reduced width, then rolled up so as to constitute intervals between each of said widths. If this solution makes it possible to remedy the aforementioned drawback of ventilation, it generates a very significant weakening of the tensile strength of the film, so that it is not possible to wind it with sufficient tension, under penalty of rupture of the latter.

REPLACEMENT SHEET To remedy this drawback, it has been proposed to increase the tensile strength of the film, by transforming its original flat section to make it narrower, while proportionally increasing its thickness. The film obtained has very substantially the appearance of a cord.

Such a solution emerges from the teaching of patent FR 86 07908 which the applicant of this also holds. If this solution brings a very significant progress in terms of film quality, since it is possible to palletize the products in a very ventilated manner with sufficient tension of the film, without risk of breakage, a problem appears at the level of the palletizing operation as such.

Indeed, the bundle of cords resulting from the transformation is previously attached to the feet of the pallet, then helically wound over the entire height of the products by means, generally, of a palletizing machine.

A first problem appears at the level of the holding of the products on the pallet, given that the bundle of cords does not have a sufficient width to secure, in a safe and effective manner, the products located directly on the pallet, with the whole body of said pallet. Similarly, another problem may appear at the end of winding, because some cords can protrude from the height of the palletized products, so that these cords are relaxed, causing risks of breakage, taking into account the tension to which said cords are subjected. , as they are rolled up.

Finally, when the palletizing operation is finished, it is necessary to attach the bundle of cords to one of the pallet feet, after having grouped said cords. It is understood that this operation reduces the palletizing time and can sometimes be difficult.

REPLACEMENT SHEET The object of the invention is to remedy these drawbacks in a simple, rapid and efficient manner.

The problem which the invention proposes to solve is to ensure the palletization of all types of products, by means of a plastic film of the stretchable type, as defined above, that is to say with capacities of elastic stretching and self-adhesion, and this in a perfectly ventilated manner, while ensuring a perfect joining of all the products on the pallet.

To solve such a problem, a specific palletizing process has been designed which includes the following main steps:

- the film is wound up over its entire width and over at least one turn, so as to secure the lower part of the products with the pallet; - The film is cut into at least two widths which are subjected to an operation capable of transforming their section to increase their resistance;

- the widths thus transformed are wound over almost the entire height of the palletized products; - the cutting operation is stopped to again obtain the entire width of the film;

- we wind the end. in its entire width over at least one turn, on the upper part of the products.

Advantageously, after having wound the film under the above-mentioned conditions up to the level of the upper part of the palletized products and in order to improve the good performance of the products, the entire film is again wound from the upper part to the level from the palette.

REPLACEMENT SHEET Such a problem is solved in that after the step corresponding to the laying of the film in its entire width and on the upper part of the products:

- The film is cut into at least two widths which are subjected to an operation capable of transforming their section to increase their resistance;

- the widths thus transformed are wound over almost the entire height of the palletized products;

- the cutting operation is stopped to again obtain the entire width of the film (F);

- the film is wound up over its entire width over at least one revolution, on the lower part of the products.

For the implementation of the method, a device is used which comprises: - at least one reel receiving the film;

- Means capable of cutting the film into at least two widths;

- means capable of ensuring the transformation of the widths to increase their resistance;

- Means capable of ensuring the displacement of the reel and of all of the cutting and processing means having regard to the height of the products to be palletized;

- Organs for temporarily retracting the cutting means as a function of the palletization phase considered.

To solve the problem posed of obtaining, from the base film, a plurality of widths, the cutting means consist of at least one blade mounted on a pivoting arm controlled by a control member to set or not the cutting edge. the at least one blade in contact with the film.

REPLACEMENT SHEET The problem posed of ensuring the transformation of the widths in order to obtain a plurality of cords having a high tensile strength, is solved in that the means of transformation of the widths consist of profiled studs and stages delimiting two by two a profiled groove into which automatically engage, as the film unfolds, the cut widths.

Advantageously, to resolve the problem posed of transforming each of the widths into a cord, the blade or blades are arranged very substantially in the axis of the thickness of the studs.

Depending on the width of the film and the number of widths to obtain, if X is the number of cutting blades, the number of pads will be equal to X + 2.

To solve the problem posed of being able to use, depending on the progress of the palletizing operation, either the film in its entire width, or the widths transformed into cord form, the peripheral edge of each pad is largely rounded.

In view of the problem posed, the coil, the cutting blades and the transformation pads are mounted on vertical and parallel shafts, the blades and the pads being arranged in horizontal and parallel planes.

The studs are mounted for free rotation on the vertical shaft while being driven positively or not in rotation.

The device, as defined and capable of solving the problem posed, is advantageously applied to a palletizing device of the type of those comprising a turntable on which the pallet is positioned.

This type of palletizing device is perfectly known to those skilled in the art, in the field under consideration.

REPLACEMENT SHEET The invention is explained below in more detail with the aid of the accompanying drawings, in which:

- Figure 1 is a perspective view showing products palletized according to the method of the invention; - Figure 2 is a perspective view showing an embodiment of the palletizing device adapted on a palletizing device of any known and appropriate type;

- Figure 3 is, on a larger scale, a plan view and sectional view in particular of the cutting and processing members; - Figure 4 is a partial sectional view and in schematic showing the film disposed between the cutting means and the widths processing means, before actuation of all of said means;

- Figure 5 is a sectional view corresponding to Figure 4, after actuation of the cutting means to ensure the formation of widths, and simultaneously their transformation in the form of beads in particular;

- Figure 6 is a partial perspective view showing schematically the main elements of the device according to the invention, after transformation of the widths in the form of cords;

- Figure 7 is a schematic view showing the successive and continuous phases of film transformation by means of the device;

- Figures 8,9,10 and 11 show, in schematic views, the main phases of operation of the device.

As indicated, the palletizing device according to the invention can be applied to all types of palletizing devices perfectly known to those skilled in the art and capable of ensuring the automatic palletization of the products. Figure 2 shows a non-limiting example of this type of device, generally designated by (A). Essentially, this device comprises a turntable (P) on which the pallet (PA) is placed. The plastic film reel (F) is mounted with capacity for

REPLACEMENT SHEET guided vertical movement in relation to a column (Al) of the device, to be moved over the entire height of the palletized products.

The plate (P) being positively controlled in rotation, it is understood that the combined movements, on the one hand, of rotation of the pallet and, on the other hand, of movement in height of the film, ensure a helical winding of the film around the palletized products.

According to the invention, the problem which the invention proposes to solve is, in a first step, to wind the film (F) over its entire width, over at least one turn, so as to secure the lower part goods (M) with the pallet. In a second step, the film (F) is cut into at least two widths (FI) which are subjected to an operation capable of transforming their flat sections to increase their resistance and obtain a product which has very substantially the shape of a bead (F2) (Figure 7).

The bundle of cords thus obtained is moved in height to be also wound up to the upper part of the palletized goods. Arrived at this level of palletization, the film is again used in its entire width to be wound on at least one turn.

Advantageously, the reel is then lowered again after having cut the film (F) into widths (FI), then, simultaneously transform their sections into cords (F2), to arrive at the level of the pallet feet. The film is then used across its entire width to be wound up on at least one turn, then cut so as to complete the palletizing operation as such.

To solve such a problem, a device has been designed which can be applied to all types of palletizing apparatus such as that defined above and illustrated in FIG. 2.

SHEET

REPLACEMENT Essentially, the system includes:

- at least one coil (1) receiving the film (F);

- Means (2) capable of ensuring the cutting of the film to obtain the widths (FI); - Means (3) capable of ensuring the transformation of the widths (FI) to increase their resistance and obtain the strings (F2);

- Means (4) capable of ensuring the displacement of the reel (1) and of all of the cutting (2) and processing (3) means having regard to the height of the goods (M) to be palletized; - members for temporarily retracting the cutting means

(2).

The cutting means (2) consist of at least one blade (2a) mounted on a pivoting arm (2b). The arm (2b) is slaved to a control member to put or not, said blade or blades in contact with the film, as will be indicated in the following description (Figures 4 and 5).

Preferably, the pivoting arm (2b) has several parallel blades, arranged in horizontal planes so that the cutting part of said blades is arranged perpendicular to the film (F) so as to obtain the widths (FI). As an indicative example, in no way limiting, the cutting blades (2a) can be constituted by simple razor blades. Obviously, all of these blades are disposed in a protective casing (not shown) and arranged to allow the cutting part of the blades to overflow, under the pivoting effect of the arm (2b) and, conversely, their integration in said housing in the non-use position.

As shown in particular in Figures 4,5 and 6, the widths transformation means (FI), to obtain the beads (F2), consist of profiled studs (3a) delimiting, two by two, grooves

(3b). As will be indicated in the following description, the grooves (3b) are shaped and profiled to allow automatic engagement,

REPLACEMENT SHEET as the film unfolds (F), widths (FI) with a view to their concomitant transformation into strings (F2).

• In the example illustrated, each stud (3a) consists of flat blocks having a peripheral edge (3c) which is largely rounded. In the same way as the cutting blades (2a), the studs (3a) are mounted on a shaft (3d).

Advantageously, but not strictly limiting, the reel (1) receiving the film (F), the pivoting arm (2b) of the blades and the shaft (3d) of the transformation pads, are arranged vertically and parallel to each other. (Figures 2, 3 and 6). Likewise, the pads (3a) are arranged in horizontal and parallel planes, in correspondence with the blades (A). .

Note that the cutting means are arranged very slightly leading to the transformation pads (3) relative to the direction of stretching of the film (F).

Furthermore and as shown in particular in Figures 4 and 5, the blades (2a) are arranged very substantially in the axis Y-Y 'of the thickness of the pads.

The number of blades and studs depends on the width of the film (F), on the one hand, and on the number of cords that one wants to obtain, on the other hand. If X represents the number of cutting blades (2a), the number of studs (3a) will be equal to X + 2.

Given these provisions, it appears that after cutting the film to obtain the widths (FI), the latter, as and when the tensile force exerted on the film corresponding to the winding around the products to palletize, tend to slide automatically, under the effect of the profile of the studs, at the bottom of the grooves (3b). Note that the

REPLACEMENT SHEET penetration of the widths (FI) at the bottom of the grooves (3b) also results from the angular positioning of the entire device relative to the pallet. Indeed, according to this positioning, the film (F) is arranged relative to the pallet at an angle of attack (B), so as to cause, during the rotational drive of the pallet, which has the effect of '' ensure the film drive, an effort which tends to press the film against the transformation pads.

In addition, as the widths penetrate into the grooves (3b), there is an automatic folding of said widths, in the direction of their width, thus causing, having regard to the self-adhesive characteristics of the film. , the formation of the cords (F2).

The entire device, as described and illustrated, that is to say essentially the coil (1), the cutting blades (2) and the transformation pads (3), is mounted on a support base (4 ) to ensure its displacement in height, from the lower part of the pallet to the upper part of the palletized products. For example, this support base (4) is mounted with vertical displacement capacity guided in height, along the column (Al) of the palletizing apparatus. Note that the arrangements allowing the displacement in height of the support base (4) are not described in detail, because they may remain in accordance with those commonly used to allow the displacement of the spool alone in known palletizing apparatuses.

Obviously, the device is controlled by all types of sensors and timing systems, making it possible in particular to ensure, as a function of the palletizing phase, the angular pivoting of the blades and the displacement in height of the entire device in a sense and in the other.

The operation of the device according to the invention should be analyzed, with particular reference to Figures 8, 9, 10 and 11 of the drawings.

REPLACEMENT SHEET In a known manner, the pallet (PA) previously filled with the goods (M), is placed on the turntable (P) of the palletizing apparatus (A).

The film (F) is successively routed, via possible return members (5), between the cutting blades (2a) and the transformation pads (3a) (FIG. 3), to be brought to the level pallet feet (PA). The plate (P) is actuated to cause in a concomitant manner, the rotational drive of the pallet and, consequently, the stretching of the film causing its winding. As shown in FIG. 8, the film (F) is placed, at the start, so as to make the products and the pallet integral.

At this stage, the entire device (1) (2) (3) (4) is not moved in height to wind the film at the foot of the pallet over several turns.

The cutting means (2) are then actuated so that under the pivoting effect of the arm (2b), the blades (2a) cut the film to form the different widths (FI). As indicated, as the film (F) and consequently the widths (FI) are stretched under the effect of the rotational drive of the pallet, each of the widths (FI) is automatically positioned in the bottom of the grooves (3b) creating in a resulting manner, the cords (F2) (Figure 9). The assembly (1), (2), (3), ι (4) is then displaced in height along the palletized goods (M) thus causing the helical winding of the bundle of cords (FIG. 9).

Arrived very appreciably at the upper part of the palletized goods (M), the device (1), (2), (3), (4) is immobilized in height and the cutting blades (2a) retracted (figure 10) . It therefore appears that the film, still under the effect of the rotational drive of the pallet, is arranged in its entire width to be wound at the top of the palletized goods on a lathe, but generally

REPLACEMENT SHEET over several turns (Figure 10).

At this stage, we proceed, as indicated above, to wind helically the bundle of cords (F2) from top to bottom. For the most part, the cutting blades (2a), under the effect of the angular pivoting of the pivoting arm (2b), are again in contact with the film, for the formation of webs (FI) and simultaneously, always under the 'tensile effect of the film resulting from the rotation of the pallet, the formation of the beads (F2) (Figure 11). When the bundle of cords reaches the bottom of the pallet, the cutting blades are retracted to arrange the film over its entire width. The film is then cut, the end of the wound film being simply applied to part of the palletized products, in particular at the level of the pallet feet.

The goods thus palletized are perfectly held in position on the pallet, since the film is used at the level of the pallet feet over its entire width. The cords (F2) ensure perfect ventilation of all the goods thus palletized. The device therefore makes it possible to combine the advantages resulting from the use of a solid film, namely a very good hold between the goods and the pallet, with a film whose section has been transformed in order, firstly, to increase its tensile strength and, on the other hand, allow ventilation of palletized goods.

Note that the studs (3a) are mounted free to rotate on their vertical support shaft (3d), or else can be positively rotated in the same direction as that of the stretching of the film under the effect of the rotation of the support plate (P) receiving the pallet.

In addition, the entire device can be controlled by any system making it possible to give different tensions at the level of the film, when the latter is used in its entire width or else in the form of cords. When the film is transformed into a bundle of

REPLACEMENT SHEET cords, the tension exerted may be greater given the increase in resistance resulting from this transformation.

The advantages clearly emerge from the description, in particular it is emphasized and recalled:

- the simplicity of use of the device which can be mounted on all types of standard palletizing machines;

- the use of a standard plastic film of the stretch type having self-adhesive and elastic stretching capacities; - saving material and labor;

- a saving of material since it is possible to stretch the film as much as possible when it is transformed into strings, as opposed to packaging methods using a full film. As an indication, a palletization requiring approximately 500 grams of stretch film, uses, with the method of the invention, only about 200 grams;

- a significant gain in volume in terms of waste, the operator being able to very easily manually reduce the film laid, giving it a compact shape.

REPLACEMENT SHEET

Claims

1 / Palletizing process, of products or goods (M), from a stretchable plastic film (F), characterized by the following essential steps:

- the film (F) is wound up over its entire width and over at least one revolution, so as to secure the lower part of the products (M) with the pallet (PA);

- The film (F) is cut into at least two widths (FI) which are subjected to an operation capable of transforming their section to increase their resistance;

- the widths (FI) thus transformed are wound up over almost the entire height of the palletized products (M);

- the film (F) is wound up over its entire width over at least one revolution, on the upper part of the products.

2 / A method according to claim 1, characterized in that after the step corresponding to the laying of the film (F) in its entire width and on the upper part of the products:

- The film (F) is cut into at least two widths (FI) which are subjected to an operation capable of transforming their section to increase their resistance; - the widths (FI) thus transformed are wound from top to bottom over almost the entire height of the palletized products (M);

- the film (F) is wound up over its entire width over at least one revolution, on the lower part of the products.

REPLACEMENT SHEET 3 / Device for implementing the method according to claims 1 and 2, characterized in that it comprises:

- at least one reel (1) receiving the film (F)

- Means (2) capable of cutting the film (F) into at least two widths (FI);

- Means (3) capable of ensuring the transformation of the widths (FI) to increase their resistance;

- Means (4) capable of ensuring the displacement of the reel (1) and of all of the cutting (2) and processing (3) means with regard to the height of the products to be palletized;

- members for temporarily retracting the cutting means (2).

4 / Device according to claim 3, characterized in that the cutting means (2) consist of at least one blade (2a) mounted on a pivoting arm (2b) controlled by a control member to put or not said or said blades (2a) in contact with the film.

5 / Device according to claim 3, characterized in that the processing means (3) of the widths (FI) are constituted by profiled pads (3a) and stages defining two by two a profiled groove (3b) in which engage automatically, as the film unfolds (F), the cut widths (FI).

6 / Device according to any one of claims 4 and 5, characterized in that the blade or blades (2a) are arranged very substantially in the axis of the thickness of the pads (3a).

7 / Device according to any one of claims 3 to 6, characterized in that as a function of the width of the film and the number of widths (FI) to be obtained, if X is the number of cutting blades (2a), the number of pads (3a) will be equal to X + 2.

REPLACEMENT SHEET 8 / Device according to claim 5, characterized in that the peripheral edge (3c) of each pad (3a) is largely rounded.

9 / Device according to any one of claims 4 and 5, characterized in that the coil (1), the cutting blades (2a) and the processing pads (3a) are mounted on vertical and parallel shafts (2b) -

(3d), the blades and the studs being arranged in horizontal and parallel planes.

10 / Device according to claim 9, characterized in that the studs

(3a) are mounted for free rotation on the vertical shaft (3d) while being positively driven or not in rotation.

11 / Device according to any one of claims 1 to 10 and its application to a palletizing device of the type of those comprising a turntable (P) on which is positioned the pallet (PA).

REPLACEMENT SHEET