The present invention relates to a recreation mat that contains at least one synthetic foam sheet. This mat is used basically to provide thermal insulation from the ground for people resting or performing exercises as well as to ensure a soft cushioning surface.

There are many types of such recreation mats known from the state of the arts, featuring various forms, starting from an ordinary sleeping pad, through various mattresses, to fitness and recreation mats.

American patent application US 4574101 discloses a multi-layer fitness mat containing the external and internal layer made of closed-cell plastic foams featuring various density. The middle layer with a relatively high density is configured to form air chambers limited by the internal surfaces of external layers. The chambers can have the form of vertical cylinders or specially sized and spaced longitudinal channels. In addition, the mat can come in a version that allows for rolling thanks to a kind of hinges formed in one of the remaining layers in the place or places where other layers are interrupted.

A similar solution, for example, has been disclosed in the American patent application US 2010173124.

The common feature of majority of mats is that they are made of soft and resilient materials, which disables the mats to maintain the form shaped, instead they return to their original planar form.

The aim of this invention is to provide a recreation mat that features functionality, maintains its shape relatively efficiently and easily returns to its original planar form. The nature of the invention is a recreation mat that contains at least one sheet made of synthetic foam, characterised in that at least one longitudinal structural component inside the mat sheet having the form of metal longitudinal plastic- coated core. The term "longitudinal structural component" means, according to the invention, any component with the above-mentioned construction that consists of a core and coating, of which one linear dimension in its longitudinal axis is higher than the linear dimension measured crosswise to the longitudinal axis of component. The above-mentioned at least one longitudinal structural component preferably consists of a core having the form of longitudinal plastic coated metal sheet.

The recreation mat according to the invention preferably includes at least two longitudinal structural components having the form of basically mutually parallel longitudinal structural ribs of metal plastic-coated bar cores. Preferably, according to the invention, the mat includes at least two longitudinal structural components having the form of basically mutually parallel transverse structural ribs of metal plastic-coated bar cores.

Preferably the longitudinal structural ribs are joined with transverse structural ribs to form a plastic-coated network. In an advantageous embodiment the mat according to the invention, includes three layers having the form of synthetic foam, while outer layers are harder than the inner layer that contains at least one longitudinal structural component.

Preferably the ratio between the thickness of longitudinal structural component coating and the thickness of its core measured perpendicularly to the mat surface, in particular the ratio between the thickness of structural rib coating and the diameter of rib metal core remained within the range of 0.25 to 0.9.

Preferably, the rib metal core adopts the form of annealed aluminum or steel bars, while the rib coating is preferably made of polyethylene (PE), polypropylene (PP), polyamide, polystyrene, ABS or PVC. Particularly suitable materials to construct the mat include: polyethylene (PE) foam, especially made of cross-linked polyethylene (PEX), polyurethane or latex foam. In the case of multilayered versions, particular layers of the mat are welded together, while foam material pores pointing to the outside are closed with a melted foam layer as a result of heat treating.

The metal cores of longitudinal structural components, in particular in the form of ribs or metal sheets, make the mat rigid and after changing its shape provide relatively stable shape retention. The use of plastic core coatings of those structural components prevents cores from getting through the soft foam layers of the mat, protects the cores against excessive deformation and prevents cores from permanent bending and waves, thanks to this after bending and straightening, the cores return to their original straight-line or planar form.

Thanks to this innovative functionality the mat constructed according to the invention can be an extremely useful item of equipment for gymnastics and rehabilitation purposes, helping to do various exercises at different mat shapes. In addition, the mat according to the invention can be used as multi-purpose tourism equipment, which, depending on its shaping can be used as a lying mat with shaped headrest, seat, temporal canopy, windbreak, table or thermal screen. Finally, it can be also an item used by children to play with, as it allows for arranging various shapes.

The invention presented in an advantageous embodiment on the drawing, where particular figures show:

Fig. 1 - depicts the first embodiment of a mat according to the present invention in a top view (fig. 1a), in cross-section (fig. 1 b) and in longitudinal section (fig. 1c),

Fig. 2 - depicts the second embodiment of a mat according to the present invention in a top view (fig. 2a), in cross-section (fig. 2b) and in longitudinal section (fig. 2c),

Fig. 3 - depicts the third embodiment of a mat according to the present invention in a top view (fig. 3a), in cross-section (fig. 3b) and in longitudinal section (fig. 3c), while

Fig. 4 - depicts the fourth embodiment of a mat according to the present invention in a top view (fig. 4a), in cross-section (fig.4b) and in longitudinal section (fig.4c). The mat 1 according to the invention presented in fig .1 has a form of sheet 2 made of porous, synthetic foam, incorporating longitudinal structural components (they are melted in) in the form of two longitudinal parallel structural ribs 3. The mat 1 is made of polyethylene (PE) foam with a density of 50 kg/m ³ . Foam sheet 2 has a length (L) of 180 cm, a width (S) of 50 cm and a thickness (A) of 1 mm. Structural ribs 3 have the form of metal cores 4 covered with plastic coats 5. In the presented example core 4 has a form of annealed aluminum rod, whereas its coat 5 is made of polyethylene. The diameter D of core 4 is 5 mm, while the thickness G of coat 5 equals to 2.5 mm, which results in a total rib 3 diameter of 10 mm.

Fig. 2 depicts the second embodiment of a mat 1 ' according to the present invention. The mat 1 ' is made of multi-layered sheet 2' that includes three layers: internal layer 6 of foam with a relatively low density and two external foam layers 7 surrounding it, featuring a relatively high density. Internal layer 6 is made of polyethylene (PE) foam with a density of 30 kg/m ³ , whereas external layers 7 are made of cross-linked polyethylene (PEX) with a density of 60 kg/m ³ . Neighboring layers 6, 7 are interconnected by welding. The thickness B of internal layer 6 is 12 mm, while the thicknesses C of external layers 7 equal to 3 mm. In internal layer 6 there is a set of equi-spaced six longitudinal structural components having the form of longitudinal structural ribs 3 constructed similarly to the ribs 3 of mat 1 from fig 1 . Mat 1 ' is additionally equipped with two mutually parallel transverse structural ribs 8 with cores 9 and plastic coatings 10 and features similar construction to longitudinal ribs 3. Diameter D of each core 4 of the longitudinal ribs 3 is 6 mm, while each thickness G of coatings 5 covering ribs 3 is 1 .5 mm. The radial dimensions of transverse structural ribs 8 are the same as the dimensions of longitudinal ribs 3. The total diameter of structural ribs 3, 8 is 9 mm. The presented example of mat 1 ' has the following dimensions: 80 cm (L) x 80 cm (S).

A certain modification of the mat embodiment presented in fig. 2 can be the mat fitted with transverse cores linked with longitudinal rib cores to create a network fully covered with a plastic coating. Another embodiment of multi-layered mat 1 " according to the invention is presented in fig. 3. Mat 1 " has a similar construction to mat V presented in fig. 2 differing from it by the number of longitudinal ribs 3 and the lack of transverse ribs. Four longitudinal ribs 3 are fitted with annealed steel cores 4 with a diameter (D) of 3 mm each, covered with polyethylene coatings 5 with a thickness (G) of 2.7 mm and they are placed in internal layer 6 of polyethylene (PE) foam with a density of 40 kg/m ³ and a thickness (C) of 10 mm. The external layers 7 are made of cross-linked polyethylene (PEX) with a density of 50 kg/m ³ and have a thickness (C) of 5 mm each. Mat 1 " is equipped with handles 1 1 installed on opposite sides to make it easier to carry the mat, projecting from the shorter sides of mat 1 ", sheet 2" with the following dimensions: 80 cm (L) x 60 cm (S).

Fig. 4 shows another alternative embodiment of single-layer mat 1 "' according the invention. In this embodiment mat 1 "' includes longitudinal structural component 3"' that consists of core 4"' having the form of rectangular steel sheet with a thickness (D) of 3 mm covered by a polypropylene (PP) coating with a thickness (G) of 2 mm.

Preferably, external surfaces of the mat according to the invention were subject to appropriate heat treating resulting in creating a thin layer of melted foam to close the outer mat pores.

Although the core material for longitudinal structural components presented in the examples is annealed aluminum or steel, it is obvious that, according to the invention, it is possible to use any other alloy, particularly an alloy of steel, aluminum or copper featuring plasticity that would allow for bending sheets or rod easily by hand, especially the rods with a diameter of approx. 1 centimeter or sheets of a similar thickness.

The same applies to coating that can be made of any plastic, like, for example, polyamide, polystyrene, ABS or PVC.

In the presented embodiments the ratio between longitudinal structural component coating thickness and the thickness of component core measured perpendicularly to the mat plane, which especially for longitudinal rod structural components is a ratio between structural rib thickness G and diameter D of rib metal core, ranges from 0.25 to 0.9, which defines merely the preferably range for the ratio, not a range of values necessary to reach the aim of the invention. Mat sheets can also be made of other synthetic foams that provide proper thermal insulation properties and resilience, for example, such as other polyethylene, polyurethane or latex foams.

Finally, for the person skilled in the art it is obvious that one can use other thickness and hardness values of particular foam layers, as well as other numbers of foam layers, other numbers of longitudinal and transverse ribs, other cross-sections of rib cores than the presented circular one, other materials for metal cores and plastic coatings, other rib diameters and other coating thicknesses depending mainly on mat utility parameters, especially on its resilience. The particular layers of multi-layered mat that contact between each other can be joined using any other method than welding, such as for example gluing.

The plans presented in figures are not scaled and are for reference purposes only.

The examples presented should not be, in any case, considered exhaustive and restricting the presented invention, the nature of which has been described in patent claims.