EP0706484A1

EP0706484A1 - Load transporting pallet

Info

Publication number: EP0706484A1
Application number: EP95916574A
Authority: EP
Inventors: Hans Dr Viessmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-05-04
Filing date: 1995-04-28
Publication date: 1996-04-17
Anticipated expiration: 2015-04-28
Also published as: ES2109102T3; US5769001A; FI960001A0; CZ344895A3; FI960001A; DK0706484T3; HUT72767A; WO1995030587A1; SK296A3; DE59500804D1; NO960012D0; CA2164228A1; AU2303095A; PL311961A1; KR960703386A; EP0706484B1; ATE159225T1; JPH09504258A; NO960012L; AU679638B2

Abstract

PCT No. PCT/DE95/00571 Sec. 371 Date Dec. 27, 1995 Sec. 102(e) Date Dec. 27, 1995 PCT Filed Apr. 28, 1995 PCT Pub. No. WO95/30587 PCT Pub. Date Nov. 16, 1995A load transporting pallet made of paper, cardboard and/or cellulose fiber waste is disclosed. In order to improve the carrying capacity of such pallets, a supplementary reinforcement layer made of recyclable material is arranged between both layers that form the carrying surface and the mounting fee. The reinforcement layer is provided with passages distributed throughout its whole surface and through which the top and bottom layers are interconnected by their opposite rough surfaces.

Description

Pallet for the transport of loads

The invention relates to a pallet of paper, cardboard and / or cellulose fiber waste for the transport of loads.

Such double-layer pallets are known, for example, according to German utility model 94 13 164, which are produced by the suction molding process. For further relevant prior art, reference is made to the following publications:

German utility models 91 00 014 and 73 03 502 and also to the German patent 29 18 573 C2. With regard to the suction molding process, reference is made to European patent 0 616 076 and US patent 867,389.

It remains to be seen what the load-bearing capacity of the pallets according to German patent 29 18 573 C2 and German utility models 91 00 014 and 73 03 502 is. However, if the pallets are manufactured using the suction molding process, which is very advantageous per se, they leave something to be desired in terms of their resilience. The pallet according to German utility model 94 13 164 can also be reinforced, for example, by double-layering, but it has been shown here that the layers cannot be connected to one another sufficiently firmly. This problem would also arise if one wanted to provide an intermediate layer which increased the strength between the molded articles produced according to US Pat. No. 867,389, because molded articles produced by the suction molding process always have a relatively smooth, firm side which reflects the suction screen structure and a rough, i.e. fibrous side. Only these rough sides can be connected to one another sufficiently firmly, as is also used in US Pat. No. 867,389.

The invention has for its object to provide a pallet that can be manufactured using the suction molding process, which can also be loaded with larger loads and whose layers are firmly connected to one another despite the use of the suction molding process. This object is achieved according to the invention with a pallet, which consists of a wing formed from two layers with molded on the bottom, open to the wing, cup-shaped feet, wing and feet made of recyclable paper, cardboard and / or cellulose fiber waste in the suction molding process are and where, and this is crucial, between the two layers forming the wing and the feet, a further reinforcement layer, also made of recyclable material, is arranged and this is provided with openings distributed over the entire surface, through which the upper and lower layers pass their rough surfaces facing each other are connected.

An embodiment is preferred in which the reinforcement layer is a layer formed from the same material as the upper and lower layers using the suction molding method, with holes and with molded support feet. Advantageous further developments consist in that the walls of the support feet of the reinforcement layer are also provided with openings, that the material of the reinforcement layer is mixed with a biodegradable binding and stiffening agent and that the upper and / or lower layer with cross and / or Longitudinal ribs are provided, which is explained in more detail.

Apart from this preferred embodiment of the pallet, other recyclable materials can also be used for the reinforcement layer, which will also be explained. However, the fact remains that the reinforcement layer has openings through which the upper and lower layers with their rough, fibrous surfaces facing each other can be firmly connected by felting, which takes place in the wet state, after which the drying follows.

The range according to the invention, advantageous further developments and the manner in which it is produced are explained in more detail below on the basis of the drawing of exemplary embodiments. It shows

Fig. 1 shows a longitudinal section along line I-I in Fig. 2 by a

Embodiment of the pallet;

FIG. 2 shows a top view of the pallet according to FIG. 1;

Fig. 3 shows a section through the pallet along line III-III in

Fig. 2;

3A is an enlarged section along line IIIA-IIIA in

Fig. 2;

4 shows in perspective two web sections of the web grid;

5A-C in section (A), partial section (B) and side view (C)

Feet of the pallet;

6A, B show a partial section through the pallet in another embodiment;

7 is a plan view of a detail from a cardboard blank forming the reinforcement layer;

8 shows in section and in view a cardboard blank in the form of a sleeve for pallet feet according to FIG. 6A;

9 shows a section through the pallet in a preferred embodiment;

Fig. 10 is a plan view of the reinforcement layer of the pallet

Fig. 9;

10A greatly enlarged a section through a connection area along line XA-XA in FIG. 9; 11 is a perspective view of a further embodiment of the pallet.

Fig. 12 shows a section through the pallet along line XII-XII in

Fig. 11;

13 is a side view of a system for the production of the pallet;

14 in section and enlarges the immersion tank of the system according to FIG. 13.

15 is a perspective view of the three layers before they are joined and

16 is a perspective view of the three layers according to FIG

Put together.

The following is required for the whole:

The suction mold surfaces S of the suction molds 108 and 109 shown in FIGS. 13 and 14 correspond to the shapes of the layers 1 and 2 forming the pallet shown in FIGS. 1-6B and 9, 10. These layers 1 and 2 are designed such that on the one hand, they can be lifted off the suction mold surfaces S and, on the other hand, they can be inserted into one another. The resulting wall depressions WT of the lower layers 2 are not present on the suction mold surface S of the lower suction mold 109, but only arise when the two layers 1 and 2 are pressed together with the respective reinforcing layer 5. The suction molding process itself requires no further explanation, since it is known in principle , where molded bodies (here the two layers 1 and 2) result which have a largely smooth side (reproduction of the sieve structure of the suction mold surface S) and a rough side. With their rough surfaces facing each other, the layers 1 and 2 are also joined together with the reinforcement layer 5, i.e. the pallets provided with reinforcement have smooth surfaces on the outside.

For the pallet according to a first embodiment, reference is made to FIGS. 1 to 4. It is important for this pallet that the reinforcement layer 5 is formed from a web grid 7 from webs 8 which are rectangular in cross-section and with their main axis 8 ″ oriented perpendicular to the wing 3, with the grid 2 of the web grid 7 corresponding to the grid in the lower layer 2. grooves 9 are formed, which correspond in cross section to the height H and width B of the webs 8 (see Fig.3.

4, the webs 8 forming the web grid 7 are provided with plug-in slots 8 'arranged in the grid spacing. These webs 8 have a height H of, for example, 25-35 mm and a width of, for example, 5 mm and can also be provided with openings 6. Instead of cardboard, these webs can, for example, also be formed from hardboard cuts, which, however, since this material can only be bent to a limited extent, cannot be used for the reinforcement sleeves 10 to be integrated into the support feet 4. In order to additionally reinforce the support feet 4 against the vertical loads occurring there, the lower layer 2 in the neck region of its support feet 4, evenly distributed over its circumference, is advantageously provided with short hollow ribs 11 pointing outwards. As indicated by dashed lines in FIG. 5C, inward-pointing hollow ribs 11 'can also be provided, which can extend over the entire height H ₁ . The outward-pointing hollow ribs 11 are dimensioned somewhat longer than the height H of the webs 8, these hollow ribs 11 forming attachment stops when stacking such pallets (see FIGS. 5A, B), which facilitates the removal of the individual pallets from the stack, which would otherwise be without such attacks can be compressed too tightly and are difficult to separate.

The web grating 7 is illustrated in FIG. 2 with dash-dotted lines and conveys high deflection stability to the entire range, since the individual webs 8, since they are oriented vertically with their main axis, have a high bending resistance moment in this direction. Advantageously and as can be seen in particular from FIG. 3A, two web strips are placed next to one another for a lattice web, so that there is a greater width for the dimensioning of the receiving grooves 9 on the suction mold for the lower layer 3, with the required suction pressure in such a wide groove can also have a better and more extensive effect, apart from the fact that such wide grooves on the suction mold can also be implemented more easily. In the area between the webs 8 and also the edge areas R, the two the layers 1, 2 with their rough surfaces when the web grid 7 is inserted, which is crucially important so that the two layers 1, 2 can become matted or bonded to one another in this area during pressing. The free spaces of the web grid 7 thus form the openings 6 in this exemplary embodiment.

The embodiment according to FIGS. 6, 7 differs from the one described above in that a blank 14 made of cardboard or hard fiber material is arranged between the two layers 1, 2 forming the pallet body K, namely in the wing 3, and this, the neck necks 12 the feet 4 are at least partially provided with recesses 6 "(FIG. 7), are provided with holes or openings 6, for which a diameter of approximately 20-35 mm has proven to be expedient in view of a sufficiently firm ply connection 6A (which also applies to the above-described embodiment) with a reinforcing sleeve 10 between the layers 1, 2. In order to achieve the perforated blank, which as a flat structure, it has a lower bending resistance moment has as the above-described web grid 7 to give the same or approximately the same bending resistance moment, see In the lower position, two receiving grooves 9 are formed, into which the webs 8 arranged on the blank 14 engage, which webs 8, as shown in FIG. 6B, are, for example, angularly bent cardboard strips which are suitable (e.g. by clipping or gluing) with the blank.

The embodiment according to FIGS. 9 and 10 is preferred. According to this, the reinforcement layer 5 ′ shown in plan view in FIG. 10 is a layer formed from the same material as the upper and lower layers 1, 2 by means of molded-on support feet 4. Around this To provide reinforcement layers with greater strength, their material is advantageously mixed with a biodegradable binding and stiffening agent, for which, for example, wheat or rice starch is suitable. It is very important for the whole, and this applies to all embodiments, that the layers 1 and 2 are pressed together, including the reinforcement layer 5, in the wet state, so that the rough surface areas of the layers 1 and 2 facing each other in the openings 6 of the reinforcement layer 5 are good can be felted or tangled with one another, as is illustrated in a greatly enlarged manner in FIG. 10A. The smooth, only the

Areas of layers 1 and 2 and reinforcing layer 5 having suction strainer structure are designated by F and the rough surfaces by F ₁ and the connecting area by V. This also applies to the embodiment according to FIGS. 11 and 12, in which the reinforcing layer 5 is also in the Suction molding process is made. In this embodiment, the pallet also consists of the two layers 1, 2, on which in the Eσk areas the cup-like upright feet 4 are also formed. In addition, longitudinal and transverse ribs 15, 16 which intersect at the two layers 1, 2 are present. This rib structure shown is only an example, ie significantly more ribs can be provided in closer association with one another, it also being possible to occupy only selected areas with a denser rib arrangement. Ribs can also be arranged along the pallet edges. Not shown is a design option in which the rib structures on the two layers 1, 2 are arranged offset from one another, since this is easily conceivable. If and as shown, the upper layer 1 is provided with such longitudinal and transverse ribs 15, 16, these or the pallet can be covered with a cover layer 17 which is suitably firmly connected to the pallet, for example by gluing, crimping o. Like. In order to maintain the stackability of such pallets, which is usually always required for storage and transport reasons, the top layer 17 is provided with cutouts 18 so that the feet 4 of the subsequent pallet in the openings 19 of the pallet below can intervene. The size relationships of the sectional view in FIG. 12 correspond approximately to the actual conditions, ie the wall thicknesses of the layers 1, 2 and the reinforcement layer 5 which can be achieved by the suction molding process are approximately 5 to 10 mm. It is essential that the longitudinal and transverse ribs 15, 16 and 15 ', 16' none Hollow ribs HR are, as is also indicated by dashed lines in FIG. 12, since such ribs, although also applicable, are not as stable as the "solid ribs" actually provided here, which are formed when the suction strainer is designed accordingly, ie, the grooves in the suction strainer must be dimensioned both in width and in height so that the grooves can fill up completely during the suction molding process.

The plant for the production of the pallets is now described in a preferred embodiment according to FIG. 13, specifically with reference numerals from 100 onwards, with which a sculpture tank is designated, which is connected to lines 101 via a premixing basin 102 with an immersion container 103. Excess water is returned through a line 101 'to a water tank 104 which is connected to the premixing basin 102 through a line 102'. In a system frame 105 guides 106 are arranged above the immersion tank 103, on which two holders 107 for upper suction molds 108 are slidably guided. These suction molds 108 are attached to the holders 107 so that they can move up and down. A lower suction mold 109 is also arranged to be movable up and down in the immersion container 103, behind which there is a transfer section 110, in which finished pallets are transferred to a conveyor belt 111 which runs through a drying tunnel 112. In front of the immersion container 103, there is a feed device 113 for the reinforcement layer 5 'according to FIGS. 9 and 10 in the installation frame 105, which is also produced in another immersion container, not shown here, using the suction molding method, the powder liquid of which is mixed with the aforementioned binder.

For the shaping of the upper and lower layers 1, 2, the two suction molds 108 and 109 are fully immersed in the pulp 114 located in the immersion container 103, but are at a sufficient distance from one another in order to be able to mold the two layers 1, 2 by suction. During this process, a reinforcement layer 5 is provided in the feed device 113. After the upper layer 1 has been sucked in and shaped, the upper suction mold 108 is moved out of the immersion container and moved over the feed device 113 and pressed onto the reinforcement layer 5 located there. while maintaining negative pressure on the suction mold 108. Now the upper layer 1 and the reinforcement layer 5 'sucked in are adjusted again via the immersion container 103, immersed and pressed onto the lower layer 2, which sits on the lower suction mold 109. When lifting the three layers together, the negative pressure on the lower suction mold 109 is initially fully maintained in order to draw down as much water as possible from the now three-layer molded body. After being lifted out of the immersion container 103, the negative pressure on the lower suction mold 109 is switched off and the maximum negative pressure holds the now three-layer molded body on the upper suction mold 108, which is moved with its carrier 107 into the transfer path 110, and is placed on the conveyor belt 111 by pressure switching or blown off and driven into the drying tunnel 112, which the three-layer molded body leaves as a finished gap at the other end 112 '. As can be seen, there are two carriers 107 in the system, each with an upper suction mold 109. The carriers 107 and suction molds 109 are thus actuated alternately, that is, if the upper suction mold 108 with the upper layer 1 produced thereon is located above the feed device 113 for the reinforcing layer 5 ′, the three are put together after a start-up phase in continuous operation Layers in and above the immersion container 103. Then both carriers 107 are shifted to the right, the next lower layer 2 already being generated on the lower suction mold 109. While the finished pallet is being deposited on the conveyor belt 111, the upper layer 1 and the reinforcing layer 5 'are deposited on the lower layer 2, as described, and the two carriers 107 with the empty upper suction molds 108 pass over the transfer device 113 and the immersion container 103 back. The left carrier 107 with its suction mold 108 thus takes over and transfers the reinforcement layer 5 ', while the right carrier 107 with its suction mold 108 takes over the three-layer molded body upwards, conveys it into the transfer path 110 and deposits it on the conveyor belt 111.

When the two layers 1 and 2 and the reinforcement layer 5 'are lifted out of the immersion container 103, negative pressure is generated in the suction mold 108 via leixing 108' and positive pressure in the suction mold 109 via line 109 ', which results in a compression of the layers 1, 2nd and the reinforcing layer 5 'forming material is sounded.

This results in the area of the openings 6 with

WT in FIGS. 6A, 6B and 10A denoted Vanda depressions, which have a depth of about 2-3 mm. The wall thickness of the finished pallets is about 6-10 mm after leaving the drying tunnel 112.

The sectional view in Figure 12 shows a pallet part in the wet state. In the dried state, the thickness D of the hips 15 and 16 corresponds approximately to the thickness S 'of the two layers 1 and 2, and the height H' corresponds approximately to two to four times the thickness D.

In FIG. 15, partial areas of the two layers 1, 2 and the reinforcement layer 5 ′ are shown in perspective in the wet state before they are joined together, and in FIG. 16 a part of the pallet in the assembled state. The upper layer 1 represents a special embodiment, since it is provided with a relatively high peripheral edge 1 ', so that a pallet designed in this way can also be used for the transport of bulk material. As is easily conceivable, the reinforcement layer 5 'and the lower layer 2 could also be provided with such peripheral edges 1'. 15 and 16, corresponding parts are provided with corresponding reference numerals. The reinforcement layer 5 'is made on suction molds S which are designed such that this reinforcement layer 5' has the web grating 7 described above in FIGS. 1 and 2 as integral, and the lower layer 2 also integrally contains a matching negative structure made of hollow ribs 9 'With intersecting grooves 9, in which the web grid 7 fits.

Claims

Claims:

1. Pallet, consisting of a wing (3) formed from two layers (1, 2) with molded on the bottom, to the wing (3) open, cup-shaped feet (4), the wing (3) and feet (4) made of recyclable Paper, cardboard and / or cellulose fiber waste are formed in the suction molding process,

characterized ,

that between the two the wing (3) and the feet (4) forming layers (1, 2) a further, also made of recyclable reinforcing layer (5) is arranged and this is provided with openings (6) distributed over the entire surface by through which the upper and lower layers (1, 2) are connected to each other with their rough surfaces (F1) facing each other.

2. Pallet according to claim 1,

characterized ,

that the total area of the openings (6) corresponds to at least half the size of the wing (3).

3. Pallet according to claim 1 or 2,

characterized ,

that the reinforcement layer (5) is formed from a web grid (7) from cross-sectionally rectangular webs (8) oriented with their main axis (8 ") perpendicular to the wing (3), the grid of the web grid being in the lower layer (2) (7) corresponding receiving grooves (9) are formed which correspond in cross section to the height (H) and width (B) of the webs (8).

4. Pallet according to claim 1 or 2,

characterized ,

that the reinforcement layer (5) is a cardboard or hard fiber material blank.

5. Pallet according to claim 3 or 4,

characterized ,

that a form-fitting reinforcement sleeve (10) is arranged between the feet (4) of the upper and lower layers (1, 2) and this is also provided with wall openings (6 ').

6. Pallet according to claim 4,

characterized ,

that the reinforcing layer (5) is provided only on the underside with webs (8 ') which engage in the receiving grooves (9) formed on the lower layer (2).

7. Pallet according to claim 3 or 6,

characterized ,

that the webs (8) are also provided with openings (6 ').

8. Pallet according to claim 1 or 2,

characterized ,

that the reinforcing layer (5) is a layer (5 ') formed from the same material as the upper and lower layers (1, 2) by means of molded-on feet (4).

9. Pallet according to claim 8,

characterized ,

that the walls (4 ') of the feet (4) of the reinforcement layer

(5 ') are also provided with openings (6).

10. Pallet according to claim 8 or 9,

characterized ,

that the material of the reinforcement layer (5 ') is mixed with a biodegradable binding and stiffening agent.

11. Pallet according to claim 8,

characterized ,

that on the lower and / or the upper layer (1, 2) to the Surface (F) having suction sieve structure are formed towards longitudinal and / or transverse ribs (15, 16), the thickness (D) of which is of the order of magnitude of the thickness (S ') of the two layers (1, 2) and the height (H') of the two - up to four times their thickness (D).

12. Pallet according to claim 11,

characterized ,

that on the longitudinal and / or transverse ribs (15, 16) of the upper layer (1) a flat top layer (17) made of the same or a different recyclable material, such as cardboard blank or the like, is arranged.

13. Pallet according to claim 12,

characterized ,

that the top layer (17) is provided in the region of the upwardly open feet (4) with cutouts corresponding to the opening shape (18).

14. Pallet according to claim 8

characterized ,

that on the reinforcing layer (5 ') a web grid (7) is arranged with molded and the lower layer (2) is provided with a corresponding negative structure of hollow ribs (9'), in which the web grid (7) engages.

15. Pallet according to one of claims 1 to 14,

characterized ,

that at least the upper layer (1) is provided with a peripheral edge (1 ').