The object of the present invention is a multi-layer shape support of corrugated fibreboard as defined in the preamble of claim 1.

Known in the art generally are corrugated fibreboard shape supports, e.g. various manually-assembled underframes or structures with which the stacking strength or bursting strength of a box is strengthened. The aforementioned properties are achieved by folding the corrugated fibreboard into multiple layers with accordion-type folds in such a way that a number of layers of material are produced. The construction of a shape support is primarily determined by the intended use, but in addition to this the manufacture of the product must be taken into account in the design. Cost-efficiency is an essential issue, and more particularly as it relates to automation of the manufacturing of the product.

The corrugated fibreboard multi-layer shape support according to the invention is intended for reinforcing and making stouter various package boxes, more particularly the structure of the packaging box. The multi-layer shape support functions as an underframe, additional base, side support or corner protector of a package box. The multi-layer shape support also functions independently, without a packaging box, as an underframe for products. It has many applications depending on the attitude; on the horizontal plane e.g. to replace plywood as an underframe for a product without a packaging box, in a vertical attitude inside a packaging box bring stacking strength and bursting strength, as a cushioner in a horizontal or vertical attitude inside a packaging box.

One substantial problem in solutions according to prior art has been the manual assembly of a shape support, which has slowed down the packing of products. A shape support has also been fabricated manually by glueing, so that the structure would be more durable and faster to use, but this has increased total costs. Consequently, there has been a slow uptake of shape supports, which has prevented larger production batches, which in turn has impacted the price of the product and raised packing costs.

More precisely, the invention is characterized by what is presented in the claims. In the following, the invention will be described in more detail by the aid of an embodiment with reference to the attached drawings, wherein

Figs. 1-2 present a solution according to the state of the art.

Fig. 3 presents a solution according to the invention.

Fig. 4 presents a preferred embodiment according to the invention.

The state of the art is described in Figures 1-2. According to Fig. 1 , the structure of a conventional multi-layer shape support comprises a blank 8, on the ends of which blank 8 are end surfaces 1A, 1 B and inner surfaces 2A, 2B between them. The end surfaces 1A, 1 B are folded against the inside surfaces 2A, 2B along the transverse folding lines 7. Conventionally, the assembly of a multi-layer shape support has been implemented manually by folding the end surfaces 1A, 1 B of a die cut blank 8 against the inside surfaces 2A, 2B of the blank. After that, the blank is turned around 180 degrees and the inside surfaces 2A, 2B are manually folded against each other along the transverse folding line 9. In this way the shape support is closed into its shape according to Fig. 1 either with manual locks 6A, 6B, wherein the lock 6A functions as a male part and locks into a female part 6B. Alternatively, the shape support is formed without manual locks by manually glueing according to Fig. 2. The end surfaces 1A, 1 B are manually glued against the inside surfaces 2A, 2B of the blank. After that the blank is turned around 180 degrees and the inside surfaces 2A, 2B are folded and glued against each other along the transverse folding line 9.

In the solution according to the invention it has been possible to solve this problem in a simple way. It is essential to the invention that a mechanically formed structure, most preferably a beam structure, is obtained from a die cut blank 8, which structure is die cut, glued and folded with standard machines. Generally, a conventional box with flaps is manufactured with a conventional standard machine, which box is glued at the side seams using one glue nozzle and a packaging box is formed from it. The solution according to the invention utilizes existing technology in a new inventive manner. In the solution, a number of glue nozzles are deployed instead of just one, and the finished product is not a packaging box but instead it is a multi-layer shape support. What is important is that a multi-layer shape support can be implemented as simply as possibly mechanically and without manual work phases performed by hand. The multi-layer shape support according to the invention is most preferably a beam structure, with which the structure of the packaging box itself is reinforced. It also functions independently, e.g. without a packaging box, as an underframe for some product. The structure of the shape support is formed according to Fig. 3 from the top surface 8A and bottom surface 8B of the blank 8, which comprise the inner surfaces 2A, 2B, and from the outer end surfaces 1A, 1 B on both sides of them. The folding lines 7 separate the surfaces 1A, 1 B and 2A, 2B from each other, and the folding line 9 separates the surfaces 2A, 2B. On both longitudinal ends of the top surface 8A of the blank are glueing surfaces, on which are formed glueing seams 3A, 3B, and also with the blank turned 180 degrees according to Fig. 3 to the other side of the blank, a glueing seam 10 is formed on the bottom surface 8B. The end surfaces 1A, 1 B are folded against the inside surfaces 2A, 2B along the transverse folding lines 7, and they are glued into attachment along the glueing seams 3A, 3B. After that the blank is turned around 180 degrees according to Fig. 3 and the inside surfaces 2A, 2B are folded along the transverse folding line 9, glueing into attachment at the glueing seam 10. According to what is presented above, the multi-layer shape support is formed without manual work phases in such a way that a first standard machine glues with two nozzles the glueing seams 3A, 3B onto the ends of the top surface 8A of the blank. After this, the end surfaces 1A, 1 B are folded against the inside surfaces 2A, 2B along the transverse folding lines 7 with guide pieces in the machine. After that, a second standard machine glues with one nozzle a glueing seam 10 onto the end of the bottom surface 8B of the blank that is turned 180 degrees. After this, the inside surfaces 2A, 2B are folded against each other along the folding line 9 into the finished structure with a guide piece in the machine.

According to Fig. 3, by utilizing glueing seams it is possible to fabricate sheet structures and to form from them various multi-layer shape supports. Sheet structures are formed when the surfaces 1A, 1 B and 2A, 2B are folded against each other and in this manner an advantageous multi-layer beam structure is achieved. In addition to what is presented above, utilizing a glueing seam 3A, 3B, 10 enables easy assembly of the structure into a multi-layer shape support. In this way, the multiple layers bring additional bursting strength, torsional rigidity and load-bearing capability.

Fig. 4 presents a preferred embodiment wherein between the inner surfaces 2A, 2B are innermost surfaces, a base surface 4 and a side surface 5, as well as glueing seams 3A, 3B, score lines 11 and a folding Iine12, and also the top surface 8A of the blank 8. By means of these innermost surfaces, the base surface 4 and the side surface 5, as well as the score lines 11 and folding lines 12, various partially glued supports, e.g. corner protectors, can be formed on a case-by-case basis from the shape support according to the invention. By utilizing a production method that is per se known in the art, now it is possible to form different multi-layer shape supports by means of score lines and folding lines. By employing two or more glue nozzles according to the invention, instead of one, the glueing brings strength to the structure and facilitates assembly. When done in this manner, the fabrication of larger blanks is made possible and a multi-layer shape support is obtained in one throughput. With manual locks 6A, 6B, shape supports of different shapes can be formed in such a way that the sides are locked in the desired directions. In this way, with the production method according to the invention it is possible to make various packaging box supports, such as underframes, and transversely-installed stacking strength reinforcers; the glueing gives the structure torsional rigidity and durability. It is obvious to the person skilled in the art that the invention is not limited to the embodiments presented above, but that it can be varied within the scope of the claims presented below. Essential in the invention are the mechanically performed glueing and folding. By using two glue nozzles instead of one, and by folding the end surfaces into attachment with the inside surface, a multi-layer shape support is formed and not a normal packaging box. It is implemented with standard machines by utilizing die cutting, glue nozzles and folding axes and, if necessary, separate mechanical glueing. Glueing strengthens the structure of the inside part, the being tightly together, without increasing the consumption of material.