EP1923317B1 - Plastic pallet with anti-slip coated loading surface - Google Patents

Abstract

The pallet (1) has a loading surface (2) that is provided on a pallet main surface, where the loading surface is formed as a single piece with a slide-arrestive coating. The slide-arrestive coating is applied by injection molding, where the loading surface has a partially open structure with apertures that are limited by ribs. The loading surface is uniformly distributed, and the coating has a thickness of about 0.5 to 7 millimeters, preferably 1 to 3 millimeters. The coating is made of a thermoplastic elastomer in particular a polypropylene base. Independent claims are also included for the following: (1) a method for manufacturing a plastic pallet (2) an injection molding tool for manufacturing a plastic pallet.

Description

The invention relates to a plastic pallet for receiving and transporting goods or other general cargo.

Pallets, in particular Europool pallets (colloquially called also euro pallets) are extensively used for the transport of various goods. While wooden Euro pallets are widespread, plastic pallets are also increasingly being used. The advantage of plastic pallets is that they are significantly less sensitive to damage and easier to clean and have a very long life. Also, they have a much better resistance to environmental influences, such as moisture. In wood pallets, germs or fungi can accumulate, which is inadmissible in particular when in contact with food. A disadvantage of plastic pallets compared to wooden pallets is that they have lower coefficients of friction and thus easier to slip goods that are stacked on the pallet. To save weight, the plastic pallets generally have a plurality of apertures, which are limited by narrow ribs.

In order to reduce the problem of slippage, the plastic pallets frequently have mechanical detents in the form of point-shaped or strip-shaped elevations formed on the loading surface or a boundary edge integrally formed on the outer edge of the loading surface. These mechanical detents are disadvantageous because they must be adapted to the goods to be transported, if a corresponding anti-skid device is intended. As a result, however, the versatility is reduced, since the pallet then usually has to be used for the corresponding special goods. Also, an integrally formed on the edge of the pallet, the sliding of the goods limiting edge, the disadvantage that the loading area thereby reduced and also the removal of the goods by simply pulling off the pallet is hindered. If goods are partially parked on the elevations or the boundary, the problem of wobbling occurs, which is associated with a reduced stability.

From the publication GB 1512450 A is a plastic pallet with the features of the preamble of claim 1 is known, which consists of a lower part and an upper part, which are interconnected via profile support. The upper part has an upper cover plate which is designed as a loading surface and which is designed as a closed surface or perforated by means of a multiplicity of apertures. The openings are partially arranged close to each other, so that in this area of the cover plate, the openings are limited only by webs. On the cover plate, a lubricant of rubber in the manner of a thin layer is applied. The anti-slip coating is in the form of individual nubs or stripes. For applying the rubber layer, coating methods are proposed in which a synthetic, preferably a thermoplastic, rubber which is dissolved in a solvent is applied liquidly or in which a thin rubber layer is applied to the cover plate by means of adhesives or by heat welding. Because of the adhesion problems between the rubber layer and the surface of the cover plate, the surface of the cover plate must be additionally subjected to a surface treatment. The possible surface treatments, such as roughening by sandblasting, flame spraying, oxidation or application of a primer, are very complicated and expensive. Apart from this, due to the expected in use deformation of the cover plate - especially in the open area of the cover plate - no secure adhesion of the anti-slip layer can be ensured, which is why the coating is preferably provided in the closed cover plate on the dimensionally stable profile beams, since there the peel effect due to deformation is lower.

The DE 195 22 000 C2 discloses a plastic pallet in which a lower part is welded to an upper part and in which a non-slip coating is locally applied to the loading surface in linear regions. This is made by a multi-component injection molding, in which movable cores are provided on the tool in the region of the loading surface, which are withdrawn after the first injection molding of the production of a base pallet and subsequently the material of the anti-slip coating is injected into the groove-shaped regions formed by the cores. Since the anti-slip coated areas protrude beyond the base area of the base pallet, at the transition region from the base area to the anti-slip coated areas, edges arise in which dirt can accumulate. Furthermore arise on the anti-slip coating upwardly directed burrs. In addition, created by the movable cores increased manufacturing costs in the production of the injection mold. In addition, the universal usability is also limited here.

Object of the present invention is to provide a plastic pallet that can be used multifunctional for the safe transport of any goods, easy to clean and easy to manufacture and nevertheless includes in a simple manner a slip protection for the transported goods.

The object is achieved by the characterizing parts of claims 1, 8 and 9. Advantageous developments are characterized by the features contained in the dependent claims 2 to 7.

According to the invention, a plastic pallet is created, the loading surface of which is formed by means of a blanket coating throughout to prevent sliding. In particular, the coating according to the invention also covers the structure of the loading surface which is formed by webs or ribs.

The continuous slip-resistant design of the loading surface is preferably done by an injection-molded injection-resistant layer, which consists of plastic. As a result, an inseparable, cohesive connection of the anti-slip plastic layer is produced with the plastic pallet.

If the plastic pallet is preferably also produced by injection molding, the coating can be molded onto the plastic pallet by the same method, ie a multi-component injection molding method, and with the same tool.

The main surface of the pallet is defined by the outer dimensions of the pallet in the direction of latitude and longitude, which as a rule also represents the loading surface. The loading area can also be smaller than the said main area.

This anti-slip coating is expediently formed from a thermoplastic elastomer (TPE). The TPE may be a polypropylene based material combination. Although the base pallet, ie the plastic pallet without the anti-slip layer, is made of polypropylene, the advantage of the largely sorted plastic combination results for the recycling. Also, the base pallet of other plastics, preferably thermoplastics, such as, for example, be made of polyethylene.

When goods are placed on the loading surface of the plastic pallet, ie on the anti-slip layer, this anti-slip layer ensures that there is an increased coefficient of friction between the goods and the plastic pallet. When moving the pallet, as happens during transport by forklift or pallet truck or truck, a slip-resistant state of the goods is guaranteed. The adhesion preferably corresponds approximately to the values of wood, in particular a cut so otherwise untreated wood surface.

The surface of the pallet, in particular the loading surface, is preferably flat.

Conveniently, a roughness R, of ≤ 3mm is advantageous. In particular, smaller roughness depths of 0.5 mm and smaller are conceivable. Preferably, the roughness is selected between 0.3 and 0.7 mm, to improve the stability.

The plastic pallet may be provided not only in the area of the loading surface with the anti-sliding layer, but also in the area of the storage area to the ground and / or to the engagement surfaces of the contact surfaces of forklift tines u. Like. Transport.

In the area of the loading surface, a uniform layer thickness of the anti-slip layer of at least 0.5 mm is preferably provided, but higher layer thicknesses of about 5 mm are also possible. Preferably, the layer thickness is about 1 and 3 mm.

According to the invention, a method for producing a plastic pallet according to one of claims 1 to 7 is provided, in which a base material is injected into an injection molding tool in a first injection molding step, thus producing a base pallet with a loading surface and in a subsequent working step by retracting a displaceable part of the injection molding tool comprising a portion of the tool forming a loading surface of the base pallet as a whole, creating a single-cavity, into which the material is injected for full coverage coating of the loading surface.

The plastic pallet is preferably made of two materials and can be produced in an injection molding process. In this case, a basic pallet is produced in a first step. This basic pallet has essentially the shape of the Euro pallet and is designed so dimensionally stable that it can safely pick up the load of goods. Advantageously, the sliding-inhibiting region is integrally formed integrally with the same tool by means of a multi-component injection molding process on the base pallet. In terms of production technology, in the multicomponent injection molding tool, a movable punch is provided, which is initially in an inner position, so that the base pallet is produced when the first plastic is injected. In a subsequent step, the movable punch is displaced outward by a defined area so that a cavity is formed between the base pallet and the displaced core, into which the second plastic is injected. The second plastic is the material from which the slip-resistant layer is formed. In this case, a cohesive connection is achieved between the base pallet and the anti-sliding layer. This means that preferably by a kind of melting of a portion of the base pallet, the slide-inhibiting layer is inseparably connected to the base pallet.
The size of the displaceable punch corresponds to the entire pallet area, in particular the loading area. This has the advantage that the entire cargo area is covered with the anti-slip layer, which ensures that any goods can be safely transported and the range is thus universally applicable.

Fig. 1

eine erfindungsgemäße Kunststoffpalette

Fig. 2

die unterschiedlichen Beladungsmöglichkeiten der Kunststoffpalette

In the following the invention will be described with reference to drawings. Show it:

Fig. 1

a plastic pallet according to the invention

Fig. 2

the different loading possibilities of the plastic pallet

In Fig. 1 For example, the pallet is shown as a Euro pallet. This usually has the dimensions 1200 x 800 x 144 mm and is essentially cuboid. The overhead surface is the main pallet surface. On the main pallet surface, also referred to below as loading surface 2, the goods to be transported are stacked. In the illustrated performance example, the loading surface 2 corresponds to the said main surface of the pallet. The main surface of the pallet has a small radius at the edges. However, the edges in the height direction of the pallet are characterized by a much larger radius. The loading surface 2 is flat and continuously coated with a non-slip layer throughout. In addition, the loading surface 2 has a plurality of openings. As a result, a load-bearing three-dimensional structure is formed which generates a high load-bearing capacity combined with the least possible use of material. The apertures of the loading surface 2 are open, but it is also conceivable that at least partially closed recesses are provided. The geometry of the apertures is expediently dimensioned such that impermissibly large accumulations of material are not formed at any area of the plastic pallet.

As the FIG. 1 shows the openings are rectangular and close to each other close to each other, so that the loading surface 2 is formed at these points only by the narrow web-like connections between the openings. The width of these webs or ribs is 2 to 6mm, in particular about 3mm. Advantageously, the anti-sliding coating is also pulled slightly over the edge region of the ribs or webs, so that the upper region of the rib or web walls is likewise coated in particular at the edge region. In the area of the outer edges areal smaller openings or depressions are formed. Furthermore, in the area of the outer edges, the areal proportion of the depressions is smaller, which means that more plastic material is provided here, and that the pallet is thus reinforced at the edges. These narrow bars are coated.

The loading surface 2 opposite is the storage area 3, which, if necessary, has a sliding-inhibiting layer.

Pallet trucks or forklifts are often used to move the pallet. These have two forks which engage through openings in the plastic pallet in the four sides adjacent the loading surface 2 to lift the pallet. The Contact areas at which the forks of a forklift attack on the plastic pallet 1 are referred to below as transport surfaces 4. These transport surfaces 4 are located in the region of said lateral openings of the pallet and point downwards. Also on the transport surfaces, a sliding-inhibiting layer is preferably provided.

Fig. 2 shows different ways in which the plastic pallet can be loaded with goods. Fig. 2a, 2b and 2c show that different beer barrels 10,11,12 can be safely on the pallet. Since the diameter of the barrels in the area of the footprint between Fig.2a and Fig.2b is different and under Fig. 2c a larger number of smaller barrels is transported, the advantage of a flat loading surface 2 lies in the fact that there are no elevations on which some of the goods may only partially stand, so can wobble and slip easily. Likewise, as in Fig. 2d shown beer crates 13 can be safely taken. Due to the flat loading surface 2, which is designed to prevent sliding, so the advantages of universal applicability of the plastic pallet 1 with a secure state of the goods are connected.

Claims (9)

1. A plastic pallet (1) for transporting products or other bulk cargo with a loading surface (2) provided on the main surface of the pallet, which loading surface at least partially comprises an open structure with a plurality of openings closely adjacent to one another, wherein the loading surface (2) in the portion of the open structure is formed by narrow bars or ribs between the openings, wherein the loading surface (2) is continuously provided with anti slip properties through a coating extending over its entire surface.
2. A plastic pallet according to claim 1, wherein the material from which the coating which extends over the entire surface is formed, is a plastic material.
3. A plastic pallet according to claim 1 or 2, wherein the ribs or bars of the loading surface (2) are formed with a width between 2 and 6 mm, preferably approximately 3 mm.
4. A plastic pallet (1) according to one of the claims 1 to 3, wherein the coating covering the entire surface laterally overlaps an upper edge portion of the ribs and bars.
5. A plastic pallet (1) according to one of the preceding claims, wherein the loading surface (2) is configured flat, in particular continuously flat or planar.
6. A plastic pallet (1) according to one of the preceding claims, wherein the coating extending over the entire surface comprises a coating thickness of 0.5 mm to 7 mm, preferably 1 mm to 3 mm.
7. A plastic pallet (1) according to one of the preceding claims, wherein the coating which covers the entire surface is made of a thermoplastic elastomer, in particular a material combination on the basis of polypropylene and/or the plastic pallet comprises a base pallet, which is made of polypropylene or polyethylene.
8. A method for producing a plastic pallet according to one of the claims 1 to 7, in which a base material is injected into an injection molding tool in a first injection-molding step to produce a base pallet, and a continuous cavity is created in a subsequent step by withdrawing a movable stamp by a predetermined amount, which stamp is provided movable in the injection molding tool and whose size is equal to the entire loading surface (2) of the base pallet, into which cavity the material for the coating which covers the entire loading surface is injected.
9. An injection molding tool for producing a plastic pallet (1) according to one of the claims 1 to 7 or for performing the method according to claim 8, in which a movable stamp, starting from an inner position, in which a first plastic material for producing a base pallet can be injected, can be shifted outward by a predetermined amount, so that a cavity is created between the base pallet and the moved stamp, into which cavity a second plastic material can be injected, wherein the size of the movable stamp corresponds to the entire loading surface (2) of the base pallet.

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