PT98295B - PROCESS AND APPARATUS FOR OBTAINING A PALLIZED LOAD INVOLVED BY AN ELASTIC MEMBRANE WITH FOLDED OR ROLLED ORS - Google Patents

Abstract

Disclosed are palletized loads (2) formed by a plurality of packages (21) and wrapped in stretchable film (1) as well as a related process and apparatus to produce such palletized loads (2). The stretchable film (1) has strengthened sections (111, 112, 113, 211, 212) generated by folded or rolled edges (11, 12) or folded central parts and, where said film (1) connects the load (2) to the pallet (3), it has a roped lower edge (115). <IMAGE>

Description

This invention relates to the process and apparatus for making cargo packages, consisting of several units, fixed to a pallet and surrounded by an elastic membrane.

This invention relates, more particularly, to an elastic membrane with folded or curled edges, which spirally wraps a load connected to the fixation of the load to a pallet by tying the lower edge of the elastic membrane in circles around the pallet, increasing thus the stability of the entire package while reducing material consumption, the time spent in the wrapping operation and, at the same time, improves the handling of the palletized yoke.

Background of the invention

There are many different types of packaging materials useful for shipping cargo consisting of several units placed on a pallet. A more widely used type of material is an elastic membrane that involves loading the pallet. Loads wrapped in an elastic membrane are well known, as are the processes for obtaining them and the various machines necessary for carrying out such processes, however problems of stability of the complete package have often been solved with the use of extra materials , such as pressed cardboard corners and extra layers of the elastic membrane itself.

□ principle of winding an elastic membrane is that it is guided from a point of unwinding and extension involving a load by relative rotation between the load and the complement of the spiral membrane. In an execution the load is placed on a rotating table

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along a vertical axis and _{T in} this way, - wrap the elastic membrane around the load. At the same time, the elastic membrane calcium moves along a vertical path in such a way that a strip of the membrane spirals up around the load. The vertical path of the elastic membrane usually starts at one end of the load, either high or bottom, moving to the other end and returning to the starting point, to allow the next load to be packed in the same way. The rotation and the up and down movement of the vertical path together create double layers of the elastic membrane with an opposite spiral direction. However, more than two layers of elastic membrane or wide margins are necessary, especially to connect the load to a pallet, in order to ensure sufficient stability of the packaging. Good examples of such packaging, processes and devices are included for example in US-3,863.42, in UK-GB2 .063.809, in German DE-2724100 or in European patents EP-A-306573 and EP-A 22135.

Another application process consists of having a stationary load and rotating all the equipment to wrap and stretch around the load. This alternative application is often called a satellite application and is especially useful when rotating. load has problems or is impossible. Descriptions of this and other similar alternatives are presented in D.E. — 2414964, in U.S '.- apl i .411.995 or in E.P.-279.871 and are widely used in industry.

Further improvements in the technical field that have been described are all based on these two basic principles of the involvement of one. charge by an elastic membrane. However, all of them suffer from the defect of a high consumption of membrane and frequently need packaging aids to guarantee the necessary stability.

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The advances made in order to make the use of the elastic membrane more economical are described in US-4,497,159 and GB-2083002, by increasing the enlargement of the membrane it is possible to reduce the amount of membrane to be applied in each package.

Similar developments have been made allowing the use of various types of material for elastic membranes. US-4,432,185 describes the joining of the front and rear of a non-self-adhesive elastic membrane by means of a rope, to facilitate attachment of the rear end with the front end of the membrane. EP-A 32140 describes an improvement for fixing the front end of the elastic membrane by controlled winding over the front end of the membrane with successive layers of the elastic membrane.

In US-4,807,427 tying the elastic membrane material is described as the connection to a basic container thereby ensuring coverage of the base and top of a cargo packed with elastic membrane.

For loads formed by articles arranged on top of each other, US patent 4,845,920 describes tying the edges of the elastic membrane and applying them in horizontal bands, in such a way that a band joins two layers. This is done in order to take advantage of the ease of application of the elastic membrane, but it allows the aeration of the load since the strips are vertically spaced.

Finally, EP-A 298 799 describes the equipment for stretching the adhesive membrane to an extent such that the edges need to be strengthened by folding or rolling to increase their resistance to breakage. In addition, it describes how to control the amount of membrane folded or rolled around the edges, to create membrane sections allowing the cargo to be aerated.

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A? a very frequent disadvantage in the application of the elastic membrane is in order to guarantee greater stability, a large amount of elastic membrane exceeding the top of the package is necessary vertically. In addition, to ensure the secure connection of the load to a healthy pallet, several layers of elastic membrane are horizontally wrapped around the pallet and under the load units. Despite this effort, sufficient stability is often not achieved, resulting in dissatisfaction both from the supplier and the customer for having disordered loads on a pallet with an inflationary consumption of ΓΓϊ b r 5 n cR elastic. In addition, the membrane connecting the load to the pallet covers the holes in the pallet designated as hooks to move the pallets. These parts of the elastic membrane are often punctured by the load hooks, which reduces stability, creating an aesthetic disadvantage and often becoming unacceptable for automatic storage facilities.

Therefore, one of the objectives of the present invention is to provide a packaging wrapped in an elastic membrane and connected by it to a pallet with improved stability.

Another objective is to provide packages wrapped in an elastic membrane with a minimum amount of elastic membrane material and with none or a minimum of auxiliary packaging material.

Another objective of this invention is to reduce the amount of material used in the. thus fulfilling the request to reduce consumption of packaging material and improve its ecological compatibility.

It is yet another object of the invention to provide loads connected to pallets by means of an elastic membrane maintaining the pallet handling recesses.

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Ί. 7 free of that same membrane achieving, at the same time, an increase in the respective degree of stability.

A further objective of the process of the invention is to reduce the time required to pack loads wrapped in an elastic membrane and attached to a pallet.

Summary of the Invention

The present invention relates to the way of packaging a number of units connected to a pallet surrounded by an elastic membrane extended in a spiral, to stabilize the load and, at the same time, connect it to the pallet. To achieve this, the elastic membrane has folded or rolled edges that stabilize the loads by wrapping them in a spiral and a lower edge tied with a rope, when wrapping in the transition zone between the load and the pallet. The tied bottom edge is distinguished from the folded or rolled edges in having more layers of elastic membrane than the folded or rolled edges.

In a preferred form the tied bottom edge should be 3 to 10, more preferably 5 to 10 times the amount of elastic membrane used for the folded or rolled parts of the edges.

Also in a preferred form the folded or rolled edges of the membrane are made less than 30 mm more preferably 10 or Ξ0 mm wide in the elastic membrane.

Also in another preferred form, the package is characterized by having the bottom edge tied, located around the top part of the pallet, at a height sufficient to prevent it. elastic membrane string or the membrane itself extends to the load, and is damaged by the load hooks that are normally used to lift the pallets.

In general, packaging may include any of the usual packaging aids such as, for example,

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CM 335 example »is not limited to top to bottom coverings - layers of separation sheets, corner stabilizers or soft protectors in sharp places, embc- = in most cases such auxilies can be dispensed with

Brief Description of Figures

We believe that the present invention will be better understood following the detailed description of the figures. The attached figures are designated to identify identical or similar elements of the description »

In the figures:

Figure 1 shows a loose piece »of the elastic membrane M) having a top edge (11) and a bottom edge (12).

Figure 2 shows the. load (2) formed by several units (21) reur.icss on a pallet (3) and wrapped in a spiral by the elastic membrane (1) of acorc: with known techniques, however only after the first ··? half of the winding has been done, from top to bottom, A = edges of the elastic membrane (11, - (2) are smooth and the netting:

between the load (2) and the pallet (3) it is obtained envelopes - ;;, horizontally several times the lower bands (123) of the smooth elastic membrane D, which passes over the passage of the load to the pallet »thus covering the palette recesses (31).

Figure 2 shows a loose part of the elastic membrane (1) with the upper edge (111) and the bottom · (112) folded, as used in the invention and wrapped around the load (2).

Figure 4 shows a separate different section of the elastic membrane (1) differently as ₅ used n the invention, with the upper edge (111) and lower (115) folded to connect the load (2) to the pallet (3).

Figure 5 shows the preferred form of the invention, however only after the first half of the wrapping has been done, from top to bottom in the load (2) is

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I 1 ₁ Jbi ^ · iQyi> / wrapped by the elastic membrane (1) with the folded edges, as shown in figure 3, the connection between the load (2) and the pallet (3) being made with the elastic membrane (1 ) as shown in figure 4.

Figure 6 shows an alternative to the elastic membrane as shown in figure 3, with the upper edge (211) and the lower edge (212) rolled up.

Figure 7 shows another alternative to the elastic membrane (1) as shown in figures 3 and 6 with the folded top edge (111) and a Z-fold in the center of the membrane.

Figure 8 shows the principle of the process as it was typically used before, for stretching the elastic membrane (1), guiding it through a pair of rollers (41,42) that rotate at different surface speeds, the roller being lower (42) faster than the upper roller (41). Also shown are other rollers that guide the membrane from the unwinding section (401) to the load application (402).

Figure 9 shows the process for creating upper (111,211) and lower (112,212) folded or rolled edges. The equipment for folding or curling 51, 52 forces the edges of the elastic membrane (11,12) to fold or curl to form the folded or curled edges of the membrane (111,211,112,212). The placement of the equipment (51,52) on top of the drawing rollers (41,42) is a preferred form. The tying equipment (6) is shown in an off position.

Figure 10 shows the process for creating a folded top edge (111) and a knotted bottom edge (115). D tying equipment (6) binds the elastic membrane (1) to such an extent that the folding or rolling equipment (52) does not reach the lower edge (12).

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11. juit. fc »Detailed Description of the Invention; and Preferred Shapes

Production Aspects of the Invention

The charge (2) consists of a variety of units (21) which are often packages of several subunits. The load (2) is wrapped in a spiral by an elastic membrane (1) to protect and stabilize the contents. To achieve this, individual strips of elastic membrane (1) are applied around the load (2) exceeding the previous strip, often more than 50'i of the width of the membrane, creating a unit in the total packaging,

In addition, the cargo (2) is also connected to an auxiliary means of transport and handling, the largest

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part of the time a palette (3), for increase the stability through a support structure laughs what facilitates the transportation and the handling. This can - if when the bottom tracks (123) of ca r g 3 (2) are apl i each.s horizontally, extending about load (2) and about palette (3). According with u ma pa rt e gives invention a

load (2) is wrapped in a spiral by an elastic membrane (1), with both edges folded or rolled (111,211,112,212), thus increasing its stability allowing to reduce the excessive amount of consecutive bands or their combinations. The other part of the invention is to firmly connect the stabilized load (2) to a pallet (3) by attaching the lower edge (115) of the elastic membrane (1) to the horizontal strips at the bottom of the load (123).

This knotted bottom edge (115) differs from the folded or rolled bottom edge (112) in being made with more elastic membrane material than the folded or rolled bottom edge (112).

In a preferred version the folded or rolled membrane edges (111,211,112,212) are formed by folding or rolling less than 30 mm !, preferably 863έ · 4έ

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U.B.ÍS91 / cia 10 mm to 20 mm. This has the advantages of improving stability and minimizing the width of the elastic membrane per edge.

In another preferred form the knotted bottom edge (115) of the elastic membrane (1) does not extend over the openings (31) of the pallet (3). This ensures that the elastic membrane (1) and the tied edge (115) will not be damaged when handling and transporting the pallet (3), for example, using cargo hooks or similar equipment.

The edges of the elastic membrane (111,211,112,212,115) can be folded or rolled or tied either inside or outside the load (2).

It is also possible to apply the elastic membrane (1) to the load (2) with only part of its total length folded or rolled or tied. For example, the first part of the elastic membrane can have smooth edges (11,12) to cover the package a first time with the smooth elastic membrane and the final part can have folded, rolled or tied edges (111,211,112,212,115) according to the invention or vice versa.

Another way of obtaining the stabilizing effect of the charge (2) is to bend one or more central parts of the membrane in the form of a Z, producing a Z-fold (113). This requires a more complicated process, but has the advantage of eliminating the folded or curled edges (111,211,112,212) of the upper or lower parts which, when spiraling, exceed and exert an especially high partial pressure on the load (2). it is particularly advantageous to have an upper folded or curled edge (111,211) and a Z-fold in the center (113).

The advantages of stability or reduced material consumption or combinations are independent both in the type of load (2) and in the way

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I 1. M how it is tidy. Hard or soft or even compressible units (21) that form ^- the load (2), neatly arranged or dispersed on a pallet, can benefit from this invention.

Also the loads (2) that require aeration can be packed using the invention. For example, the sufficient spiral step eliminates overlapping or sufficiently bending or winding the width of the elastic membrane to avoid overlapping successive bands of the elastic membrane (1) can be used to allow aeration.

It is also not crucial for this invention to choose a special material for the membrane. This invention can be produced essentially using any of the elastic membrane materials commonly used. Materials for elastic membranes that have a self-adhesive side are more suitable, as they help stabilize folded, rolled or tied edges.

Aspects of the Invention Process and Equipment

To pack loads (2) as previously described, the following process steps are required: Unroll the elastic membrane (1), stretch it and apply it to the load. As indicated in the first part, there are many processes and machines to accomplish this task. Typically the process involves a fixed point, from which the membrane is pulled around a roller, without movement (401) and oriented towards a first drawing roller (41) which rotates at a lower surface speed than the of a second drawing roller (42). The difference in speed produces the extension of the membrane (1), which is guided, by means of another guide roller, without movement (402) and applied to the palletized load (2), with a relative rotation of the palletized load (2) and the elastic membrane (1).

According to this invention this standard process is complemented by folding or rolling

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or by tying the edges of the membrane (-11-1,21-1, -112,212,115) to obtain the stretched elastic membrane (1) necessary for this invention. Placing non-standard pieces of equipment, such as a roll-up or folding plate or a folding bar (51,52,6), as an obstacle to the path of the membrane edge (11,12), gradually folds the edges of the membrane (11,12) thus producing the desired result (111,211,112,212,115). The depth and angle at which these pieces of standard equipment (51,52,6) are placed, in the path of the edges of the membrane (11,12) are decisive when folding, wrapping or tying are carried out. Therefore, the desired configuration of the membrane edge can be easily defined taking into account the characteristics of the load (2), the membrane (1) and the handling needs.

To achieve folding or winding of the edges of the membrane (111,211,112,212), when the load is rolled up (2) and the edge of the lower membrane is tied. (115) when the load (2) is connected to the pallet (3) a controller device triggers the equipment to bind only during the time when the bottom strips (123) are produced. The controller is not shown in the figures, but it can, for example, be a mechanical, electrical or magnetic sensor, combined with a suitable activator to move the tying equipment. A preferred method is to use a purely mechanical sensor / activator combination.

As it is more noticeable from the example, the application of this process and the equipment will take the additional advantage of reducing the time needed to wrap the load (2) with the elastic membrane (1), due to the reduced number of strips around the load (2) and the reduction of overlap between successive bands.

For this process it is not essential the position of the membrane to fold, curl or tie the edges,

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Along the way, however, folding devices of the elastic membrane band have been found. It will not be much more advantageous to have and roll them (51,52) over the top of the drawing rollers (41,42) and the tying device (6) installed at the bottom of the drawing rollers (41,42).

The process can also be supplemented by staples that press the edge formed by folding, winding or by tying (111,211,112,212,145) tightly together. Staples are not shown in the figures. These can be especially advantageous when an elastic membrane (1) with little or no adhesion is used.

According to the invention, a preferred process and equipment is the combination of a bottom edge, folded or rolled, with the tied part obtained using a mobile device in relation to the elastic membrane (1) or support equipment. But also as an example for loads (2) that need aeration it can be advantageous to install adjustable or mobile folding or rolling equipment (51,52).

Example

The following describes particular examples, which demonstrate, in detail, the application of this invention.

A standardized CERA Dominant satellite stretcher pack is used as the base. The loads made up of soft plastic bags are stored on a pallet. The conventional cardboard corners that are used as necessary to complete loads of this type, to give them acceptable stability, are omitted. Two bars are mounted on the satellite perpendicular to the plane of the elastic membrane with a slight angle in the direction of the membrane. The bars are installed on supports placed on top of the drawing rollers. The bars create an obstacle over a length of 15 mm, measured from the outer edge, at the

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displacement path of the elastic membrane. The bars fold the adhesive side of the edges of the elastic membrane and the fold, thus formed, is compressed around the rollers, around the drawing rollers, when the membrane is stretched. Staples are not necessary as the self-adhesive is sufficient to overcome the internal elasticity of the material.

Behind the drawing rollers is mounted on a support an hourglass stringing roller, which is driven by a lifting mechanism.

This is controlled by a magnetic means, which switches on when the electromagnetic bands are produced by connecting the load to the pallet. Alternatively, the hourglass-shaped roller can be installed on a support that will fix it at the desired height, being mechanically limited to descend further when the horizontal strips are being produced. The hourglass string, when connected, occupies 150 mm of the width of the membrane. The axis of the stranding roll is approximately perpendicular to the plane of the membrane.

The string roll, when turned on, is flush with the top of the pallet, but not above or below the level of the pallet handling recesses.

The following table shows variables and, especially, the improvements achieved with the execution of the actions according to the invention, in comparison with the results obtained according to previously known techniques. In both examples the material of the elastic membrane is polyethylene and the application apparatus is a CEKA Dominant satellite stretching and packaging machine.

In these examples, stability was assessed by placing the packages on a slope of 24% and measuring the slope of a 2 m load. in height in relation to a line perpendicular to the palette. The positive degree is given by an inclination of less than 5 cm and the negative by

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1 © cm .. Falling charges are excluded, one greater than but noted.

execution in harmony with the invention

execution done what really in a deal with The

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load thickness of. elastic membrane membrane stretch membrane width membrane width by each folded edge membrane width by each stranded edge number of membrane rolls membrane index used in total packaging total time to, wrap a pallet, efficiency index, pallet recesses degree of stability after low 2 hours of invention card but semi-folding, wrapping! ^ or folding operations. Cardboard boxes ©, © 19 mm • 172 7. 5 ©› mm • 15 mrri ©, © 23 mm

102 7.

5 ©________________ ΓΓίΟ without folded edges

12 © mm without strung edges

7.

1m. and 33 s and g, 118 7.

uncapped

100 7.

1m. and 5 © sec. 10 © 7.

capped and bored positive (even after 2 days) negative

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Soft plastic bags. elastic membrane membrane stretch membrane width membrane width by each folded edge membrane width by each folded edge number of membrane rolls used membrane index in the total packaging recesses of the. pallets uncovered auxiliary packaging not required 4 corners of degree. degree of stability after 2 hours positive (even negative, some after 2 days) times somersault

Charge

0.019

172 7. 750 mm mm

Soft plastic bags _r 023 mm

102 7.

500 mm without folded edges

120 mm without strung edges

7.

100 7.

covered and punctured

Although many preferred and optional embodiments have been described in detail, which have been illustrated by the drawings and examples, many variations are possible, which still fall within the scope of. declared invention.

Claims (9)

= CLAIMS = wool - Process for obtaining a palletized load (2), formed by a plurality of units (21) assembled in a pallet (3) and surrounded by an elastic membrane), in a spiral process, consisting of: - unroll and stretch the elastic membrane Cl) and - apply it to our palletized load (2) giving it a spiral winding, by means of the rotation of the palletized load (2) simultaneously accompanying the unfolding and stretching of the elastic membrane (15 with a vertical movement, up and to Pebble, ε which is characterized by sc along the movement of the membrane (Ί), preferably before the stretching step, both edges (111,211,112,212) of said membrane (1) are folded or rolled at the point where the membrane (1) surrounds said load (2) and attach the bottom edge (115) of the same membrane (1) that forms the bottom strips (123) of the load (2), being tied and said bottom edge being tied ( 115) consisting of a greater amount of membrane (1) than said folded or rolled lower edge (112,212). Process according to claim 1, characterized in that said folded or rolled membrane edges (111,211,112,2125 or the tied bottom edge (115) are arranged in one: additional pass through silmutaneous compression over the folds or rollers and the rope. 3® - Process according to claim 1, characterized in that the folded or rolled edges (111,211,112,212) of said membrane (15 are formed by the folding or wrapping of at least 30 mm, preferably 10 to 2.® - da width of said membrane (15. 4. A method according to any of the preceding claims, characterized in that said lower edge of the tied membrane (115) of said membrane (15 comprises a quantity of membrane 2 to 10 times, with 5 to 10 times the amount of said edge being preferable. bottom folded or rolled membrane (112.2125. 52 - Process according to any one of the preceding claims, characterized in that said lower edge of the membrane - ties (115) leaves the openings (31) in said pallet (3) uncovered. óâ - Process according to any of the preceding claims, characterized in that only a part of the total length of the aforementioned edges of the membrane (11,12) is folded or rolled or tied. Method according to one of the preceding claims, characterized in that only one of the edges of the membrane is folded or rolled (111,211,113,212) and, because at least one Z-fold (113) is provided in the central part of the. membrane (1). Sê - Apparatus for carrying out the aforementioned process of obtaining a palletized load, characterized by comprising a platform for loading, a unit for unrolling the membrane, a unit for stretching the same, an impulse to rotate the mentioned platform for the load or an impulse to rotate said unwinding and stretching units around the. said load (2), and since it includes a guide means (51,52) to bend or roll the edges (111,311,112,212) of said membrane (1) and a guide means (6) to tie the bottom edge (115) of said membrane (1), which are operated by a controller, so that said tied edge (115) remains only, surrounding said palette (3). Apparatus according to claim S, characterized in that said orientation means (51,52) for folding or rolling or said orientation means (6) for tying are folding bars, winders or folding plates. 10® - Apparatus according to claims 8 or 9, characterized in that said controller is a mechanical brake. -17775 63646 Case; CM An apparatus according to claim 8, 9 or. 10, wherein ^R ch the aforementioned guiding means forming the folded or rolled edges (111,211,112,212) are mounted on supports which allow to engage or disengage said guiding means (51,52,6). 12 - Apparatus according to claim * ?, 10, 11 or 12, characterized in that the tips of the rollers are mounted after the mentioned orientation means (51,62,6), forming the curled or folded edges (111,112).