EP2121309A1

EP2121309A1 - Floor for sports facilities

Info

Publication number: EP2121309A1
Application number: EP08709040A
Authority: EP
Inventors: Julien Waumans
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-02-15
Filing date: 2008-02-15
Publication date: 2009-11-25
Also published as: WO2008099011A1; EP1958765A1

Abstract

The present invention is related to a floor suitable for sports facilities and comprises a resilient layer (11) with on top a first and a second layer (12, 14) of a wooden material, a reinforcement mesh (13) interposed between the first and the second layers and a floor covering (15). The first and second layers and the reinforcement mesh are preferably provided in pressed panels for ease of installation. A method of manufacturing the panel and uses of the floor are also provided.

Description

FLOOR FOR SPORTS FACILITIES

Field of the Invention

[0001] The present invention is related to a floor suitable for sports halls, gymnasiums and the like. The floor complies with the technical requirements for use as a sports floor.

State of the Art [0002] Floors in sports halls should exhibit particular properties in order to meet the technical specifications imposed by law and to offer the sportspersons using such floors the necessary comfort for practising his or her sports activity. These properties may be: flatness, elasticity resulting in a high force reduction and a small energy loss, a high ball reflection, a high point elasticity (such that in case of a point load, the deformation is confined to a small area) , shock absorption, etc. For some of these properties national or regional standards exist, which may even differ for different sports disciplines.

[0003] Therefore, sports floors of the prior art usually comprise one or more elastic layers and one or more pressure spreading layers. [0004] Patent document EP 1008703 discloses a sports floor comprising an elastic layer and two thin steel plates of about 1 mm on top of the elastic layer. The steel plates act as a pressure spreading layer, while the properties of the elastic layer may be adjusted on demand to meet specific needs (e.g. a ballet floor being somewhat more elastic than a basketball floor) . [0005] However, the two thin steel plates are susceptible to plastic deformation when the necessary precautions are not taken. Sports halls sometimes are also used for non-sports occasions, such as concerts, parties etc., which require the mounting of platforms for seats, podiums, support structures for lighting etc. The components of these structures are transported on carts on the sports floor. These carts may be overloaded, or they may not have wheels with the required elasticity. This may lead to permanent deformation of the steel plates, and degrade the floor properties and usefulness.

[0006] Document DE 7911983U discloses a sports floor comprising a first elastic layer, particularly a point elastic layer, provided in between two wooden chip boards, and a second elastic layer underneath the chip boards. The two elastic layers have a different elasticity. The chip boards act as pressure spreading layers and as support layers for the elastic layers. These support layers may not be too thin, the boards would otherwise be very prone to rupture.

Aims of the Invention

[0007] The present invention aims to provide a floor for sports facilities, being easy to install, having technical characteristics at least comparable with sports floors of the prior art, but being more resistant to permanent damage due to inappropriate use of the sports floor .

[0008] The present invention also aims to provide a floor providing acoustic isolation.

Summary of the Invention

[0009] The invention is related to a floor and uses thereof, as set out in the appended claims, which can comply with the requirements for use in a sports hall, a gymnasium, etc. The invention is equally related to a panel, as set out in the appended claims, for use in such a floor and to a method, as set out in the appended claims, for producing said panel.

[0010] According to one aspect of the invention, there is provided a floor for sports facilities comprising: an elastic (or resilient) layer, a first layer provided on the elastic layer, a second layer, a reinforcement mesh interposed between the first layer and the second layer and a floor covering. The elastic layer is preferably made of a foam material. The first and second layers are made of a material comprising (or consisting essentially of) wood. [0011] The first and second layers and the reinforcement mesh form a stack on the elastic layer. Preferably, said stack consists (essentially) of said first layer, said second layer and said reinforcement mesh interposed between the first and the second layer. The first and second layers and the reinforcement mesh are preferably bonded (e.g. by adhesive).

[0012] The material comprising wood can comprise wooden chips. It can comprise wooden particles. It can comprise wood fibres. In the material comprising wood, the wood (in the form of particles, chips, fibres and the like) can be embedded in a resin or matrix or be surrounded by adhesive (e.g. chip boards, MDF, HDF, etc.). Said material comprising wood preferably comprises (or consists essentially of) wood veneer. [0013] According to a preferred embodiment of the floor of the invention, said first layer, second layer and said reinforcement mesh are provided in a multitude of panels .

[0014] According to a second aspect of the invention, there is provided a panel (or a floor element) for use in the floor of the invention. The panel comprises (or consists essentially of) : a first layer, a second layer and a reinforcement mesh interposed between the first layer and the second layer. The first and second layers are made of a material comprising (or consisting of) wood.

[0015] According to a preferred embodiment, the panel further comprises a groove and a tongue for sliding into the groove of an adjacent panel. Preferably, the length of the tongue at a frontal side of the panel is larger with reference to the length of said tongue at the side of the panel remote from said frontal side. The tongue length refers to the (length of) projection of the tongue from the panel. Preferably, the depth of the groove at a frontal side of the panel is larger with reference to the depth of said groove at the side of the panel remote from said frontal side. More preferably, the length of the tongue and the depth of the groove are larger at a same frontal side. The depth of the groove refers to the height of a wall of the groove. [0016] Preferably, said reinforcement mesh extends into the tongue .

[0017] Preferably, the panel comprises a floor covering. The floor covering is preferably made of wood. The floor covering can equally preferably be made of a synthetic material (e.g. linoleum) .

[0018] Preferably, in the floor or the panel of the invention, said reinforcement mesh is bonded to said first and second layers. The bonding can be provided by adhesive. [0019] Preferably, the reinforcement mesh is at least partially pressed into said first and second layers. [0020] According to a preferred embodiment of the invention, the first and second layers have (substantially) equal thickness. Preferably, the reinforcement mesh is provided in the middle of the panel's thickness. [0021] Preferably, the reinforcement mesh extends over the entire area of the floor.

[0022] Preferably, the first and second layer of the floor of the invention are made of plywood. [0023] The reinforcement mesh is preferably composed for at least 50% (of the area) of openings, more preferably for at least 60%, even more preferably for at least 75% and most preferably for at least 81%. Said reinforcement mesh is preferably made of metal. More preferably, said metal is steel. The reinforcement mesh is not made of (or does not comprise) wood. Preferably, the reinforcement mesh comprises one or more wires. The wires preferably have a thickness smaller than or equal to 1 mm. The wires are preferably made of steel. [0024] According to a third aspect of the invention, there is provided a use of a floor of the invention as a sports floor. The sports floor can be indoor. The sports floor can be outdoor as well. [0025] According to a fourth aspect of the invention, there is provided a use of a floor of the invention for acoustic isolation.

[0026] According to a fifth aspect of the invention, there is provided a method of producing a panel for a floor for sports facilities, wherein the method comprises the steps of: pressing a reinforcement mesh in between two layers made of a material comprising (or consisting essentially of) wood in order to obtain a panel and providing the panel with a groove and a tongue. Preferably, in said pressing step, adhesive is pressed together with said reinforcement mesh in between said two layers. More preferably, the step of providing the panel with a groove and tongue comprises one or more milling operations. Brief Description of the Drawings

[0027] Fig. 1 represents a cross-section of a sports floor of the invention.

[0028] Fig. 2 represents a layout for the installation of sandwich-type panels of the invention.

[0029] Fig. 3 represents the structure of a sports floor of the invention.

[0030] Fig. 4 represents a plan view and corresponding cross-sectional view of a preferred embodiment of the panel of the invention with tongue and groove .

[0031] Fig. 5 represents the ordering of panels and the measurement points for the tests carried out for certifying the floor of the invention as a sports floor.

Detailed Description of the Invention

[0032] Embodiments of the present invention will now be described in detail with reference to the attached figures, the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not necessarily correspond to actual reductions to practice of the invention. Those skilled in the art can recognize numerous variations and modifications of this invention that are encompassed by its scope. Accordingly, the description of preferred embodiments should not be deemed to limit the scope of the present invention.

[0033] Furthermore, the terms first, second and the like in the description and in the claims are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. [0034] Moreover, the terms top, bottom, left, right, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. The terms so used are interchangeable under appropriate circumstances and the embodiments of the invention described herein can operate in other orientations than described or illustrated herein. For example, "left" and "right" of an element indicates being located at opposite sides of this element. [0035] It is to be noticed that the term "comprising", used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, A and B are relevant components of the device.

[0036] A particular embodiment of the floor for sports facilities according to the invention is represented cross-sectionally in figure 1 and in a layer-by-layer view in figure 3. The floor for sports facilities 10 (referred to as "floor" or "sports floor" in the following) is arranged on a subfloor 1. The bottommost layer of the sports floor 10 is an elastic (i.e. resilient) layer 11. [0037] Elastic layer 11 is preferably made of a foam material with excellent point-elastic properties, such as agglomerated polyurethane (PU) foams. Agglomerated PU foams comprise floes of PU foam which are mixed with a prepolymer

(e.g. based on polyol and/or toluene di-isocyanate) and are pressed together to a predetermined density and shape (e.g. boards, panels) . A preferred agglomerated PU foam is

Agglofoam® by Agglorex, Belgium. The elastic layer should preferably ensure that deformations of the floor caused by one sportsperson are (almost) not sensed by another sportsperson playing in the neighbourhood. The stiffness

(pressure resistance) of the elastic layer can be tailored in function of the use that will be made of the sports floor (e.g. for ball sports, ballet, etc.). The foam materials used for elastic layer 11 are available in different densities. For each target use of the sports floor, a different density and/or thickness of elastic layer 11 may be chosen. Preferably, the elastic layer 11 has a density of 60 kg/m or more, wherein a density of at least 80 kg/m³ is particularly preferred and a density of at least 100 kg/m³ is most preferred. Other types of (resilient) foam materials can be used as well, such as flexible polyurethane foams.

[0038] On top of the elastic layer 11 are arranged sandwich-type panels 16. Sandwich-type panel 16 comprises three layers: a first layer or lower board 12, a second layer or upper board 14 and a (metal) reinforcement mesh 13 interposed between the two boards 12 and 14. The boards 12 and 14 are preferably made of wood, wooden chips or a similar material (e.g. plywood, medium density fibreboard (MDF), high density fibreboard (HDF) ,...). Adhesive 17 is provided around the reinforcement mesh 13. The adhesive bonds the three layers of panel 16 together.

[0039] The reinforcement mesh 13 is preferably made of metal, such as steel. It can also be made of other materials, such as carbon fibre.

[0040] The metal mesh 13 actually acts as an arming in the panel 16, allowing to keep the panel's thickness to small values. The reinforcement mesh also allows to obtain a panel which is resistant to high point loads while maintaining its (point) elastic properties. Steel is a preferred choice for the metal mesh, e.g. galvanised steel. The metal mesh may also be replaced by a mesh of any other reinforcing material, such as carbon fibre. [0041] The thickness of the panel can be so determined as to allow the sports floor to attain a good point elasticity. The floor's flexure when a sportsperson jumps and touches ground is preferably restricted to a small area around the person. For the case that plywood is used for the upper and lower boards and the mesh is of galvanised steel (see the example below for more details) , the sports floor shows a reduced comfort (less ideal point elasticity) for panel thicknesses above about 11 mm. However, the desired point elasticity can be dependent on the particular use that will be made of the sports floor.

[0042] The panel 16 can act as a load distributing (or pressure-spreading) layer. It distributes the pressure due to a point-load (e.g. a sportsperson or a ball smashed on the floor) over a larger area in order to reduce floor deformation due to that point-load. At the same time, the panel 16 can obtain an excellent point elasticity. [0043] The panels should preferably be manufactured in such a way so as to prevent warping phenomena. Therefore, providing the reinforcement mesh 13 in the middle of the panel 16 is preferable. Hence, the upper and lower boards preferably have substantially equal thickness. [0044] The term 'substantially equal' refers to thicknesses which differ not more than 10% of the total thickness, preferably not more than 5% of total thickness, more preferably not more than 2% of total thickness.

[0045] Advantageously, the upper and lower boards 12 and 14 are made of plywood. Plywood is a preferred material because it has low internal stresses, which is advantageous for preventing warping phenomena, it is highly elastic and stronger than e.g. a chip board. The use of plywood can allow to keep the thickness of boards 12 and 14 and hence the total thickness of panel 16 restricted to small values. Moreover, plywood has a relatively low coefficient of thermal expansion, which is advantageous for a sports floor extending over a large area. However, other materials may be used as well for the boards 12 and 14, such as other materials comprising wood. The materials comprising wood preferably comprise wood veneer. [0046] The panel 16 may be coated or impregnated with a humidity repelling material. This makes the panels suitable for outdoor use. Hence, the sports floor of the invention can be used both indoor and outdoor. Indoor uses are however preferred. [0047] A floor covering 15, custom to the specific sports activity to be practised on the floor is provided on top of panel 16. The floor covering 15 may be linoleum, wood or any other material suitable for the practice of indoor or outdoor sports activities. [0048] The panel 16 can comprise a top finishing layer, on top of the upper board 14, such as a layer of wood finish or parquet. This top finishing layer then acts as the floor covering 15. After installation of the panels 16, the top finishing layer may only need to be polished in order for the floor to acquire its shine and to remove any unevenness in the joints between panels.

[0049] A humidity isolating sheet 18 (e.g. polyethylene foil) may be provided in between subfloor 1 and elastic layer 11. Such a humidity isolating sheet may also be provided in between elastic layer 11 and panels 16. [0050] In order to ease the installation of the sports floor, panel 16 comprises a tongue 161 on two lateral sides and a groove 162 on the other two lateral sides. The tongue 161 is arranged to fit into a groove 162 of an adjacent panel. The metal mesh continues into tongue 161. The tongues are slid into the grooves.

[0051] An outline of the installation of the sports floor is provided in what follows. Subfloor 1 is preferably covered with a humidity isolating foil. Next, the elastic layer 11 is installed on the foil. The foam material of the elastic layer is generally provided in panels for ease of handling. These panels can have the desired thickness for the elastic layer 11 and are installed adjacent to each other on the foil. The panels of foam material may or may not be adhered to each other. The material of elastic layer 11 is generally by itself humidity resistant. Nevertheless, an isolating foil may be installed on top of elastic layer 11. Thereafter, panels 16 are installed on top. Panels 16 have a tongue 161 and groove 162. The tongue 161 of a panel is first dipped in adhesive so as to cover the whole surface of the tongue with adhesive. Next, the adhesive covered tongue is slid into the groove 162 of an adjacent panel. This way of assembly prevents the occurrence of voids in the joints between two panels. The panels may or may not be adhered to the elastic layer 11. Adherence of panels 16 to elastic layer 11 ensures that excitation of the floor by sportspersons does not cause the boards of elastic layer 11 to move (horizontally) relatively to the panels. A possible layout of panel installation (tiling) is depicted in figure 2. On top of panels 16 a floor covering of e.g. linoleum may be installed according to methods known in the art. [0052] The panel according to the invention is preferably pre-manufactured. According to a preferred method of manufacturing, the reinforcement mesh 13 is provided in between the two boards 12 and 14 and the three layers are pressed. Preferably, glue having sufficient bonding strength (e.g. two-part epoxy adhesive or polyurethane adhesive) is first provided in between the two boards 12 and 14 and/or around the reinforcement mesh. The panel, comprising reinforcement mesh, adhesive and the two boards is then pressed. A pressure of 4 MPa (about 40 kg/cm²) or higher is preferably applied to press the panel together. Said pressure is more preferably at least 6 MPa. The reinforcement mesh 13 may be at least partially (or fully) pressed into the boards 12 and 14. The manufacturing method as indicated above is preferred when boards 12 and 14 are made of plywood.

[0053] Alternatively, panel 16 may be manufactured by embedding reinforcement mesh 13 in panel 16 while the boards 12 and 14 are manufactured. By way of example, reinforcement mesh 13 may be embedded in a pulp composed of particles of wood and an adhesive matrix material (e.g. a resin) , pressing and curing the whole in order to obtain an armed board. Preferably, said board has the reinforcement mesh 13 in the middle. [0054] The panel 16 can be provided with a tongue and a groove. Tongues and grooves are preferably manufactured by milling the sides of the panel. [0055] An aspect of the armed (reinforced) panel 16 relates to its resistance to high point loads, such as may be loads produced by wheels of carts, feet of platforms mounted on the sports floor, etc. While sports floors of the prior art would be prone to plastic deformation under the circumstances set out above, the sports floor of the invention can result to be much more resistant to permanent deformation. This can be due to the reinforcement mesh and/or the combination of reinforcement mesh and first and second layers comprising wood.

[0056] A preferred embodiment for the tongue and groove configuration of a panel of the invention is represented in figure 4. Figure 4 represents a panel 46 with groove and tongue in plan and cross-sectional view. Panel 46 comprises a lower board 42, an upper board 44 and a reinforcement mesh 43 interposed between the upper and lower boards. Panel 46 is provided with a tongue 461 at two lateral sides of the panel and a groove 462 at the two remaining lateral sides.

[0057] Along tongue 461, the lower and upper edges 463 and 464 of the panel are staggered. The length of the tongue 461 at the upper edge 464 is larger than the length of the tongue at the lower edge 463. Likewise, the lower and upper edges 465 and 466 of groove 462 are staggered as well. Hence, the depth of groove 462 at the lower edge 465 is smaller than the depth at the upper edge 466. The staggering between said edges can amount to respectively half the tongue length or half the groove depth.

[0058] The benefit of the configuration of panel 46 is to increase the panel strength along the joint between two panels. Furthermore, the area where three panels join (see the layout of figure 2) results to be stronger as well.

[0059] The sandwich-type panels 16 and 46 have preferably a thickness in the range between 8 mm and 20 mm. More preferably, the thickness of the sandwich-type panels falls in the range between 9 mm and 13 mm, wherein thicknesses smaller than or equal to 11 mm are particularly preferred. The panel thickness can be determined based on the thickness and mesh size of the reinforcement mesh, the density of the elastic layer and the type of floor covering .

Description of a Preferred Embodiment of the Invention [0060] By way of example, the reinforcement mesh 13 can consist of a galvanised steel mesh (gauze) with square meshes having a side between 10 mm and 12 mm. The steel wire of the mesh can have a diameter between 0.5 mm and 1 mm. In case the boards 12 and 14 are made of plywood, they can be 5 mm thick. The total thickness of panel 16 thus does not exceed 11 mm in the present example. For ease of handling, panels 16 may be 1200 mm long and 600 mm wide. The panels can also be of square size. The tongue 161 can be 30 mm to 50 mm wide and have a total thickness of 3 to 4 mm (for a panel of 11 mm thickness) . [0061] The plywood boards with a thickness of 5 mm are composed of three layers of peeled wood (wood veneer) . The topmost wood veneer layer of the upper board may be provided in parquet style. An additional floor covering is not needed in the latter case. [0062] On a subfloor 1 an elastic layer is provided, made of agglomerated polyurethane foam. Elastic layer 11 may have a thickness of 15 mm. Panels 16 are installed on elastic layer 15. The sports floor is finished with a floor covering 15, e.g. linoleum of 4 mm thickness. The installation of a sports floor of the invention is hence easy.

[0063] Tests carried out on a sports floor according to the invention have revealed the outstanding properties. Tests have been carried out according to DIN V 18032- 2:2001-04 on a floor sample having dimensions 3.60 m x 3.60 m. The floor sample comprised: an elastic (resilient) layer made of polyurethane composite foam having 15 mm thickness, tiled sandwich-type panels having dimensions of 1200 mm x 1200 mm and a total thickness of 11 mm and comprising a tongue and groove, and a 4 mm thick linoleum covering. [0064] The sandwich-type panels comprised first and second layers of three-layer meranti plywood and a steel reinforcement mesh interposed between the first and second layers. The steel reinforcement mesh was a steel wire gauze with square meshes with sides of 12 mm. The steel wire had a diameter of 0.65 mm. The panels were ordered in staggered columns on the elastic layer, with a staggering of half a panel length, as represented in figure 5.

[0065] The sports floor was tested using the "Artificial Athlete 95" test procedure and the test climate applied was 23/50-2 as per DIN 50 014. Figure 5 illustrates the five measuring points P1-P5 for all tests and the four directions (1-4) along which the deformation spread was measured. Table 1 gives an overview of the test results and compares with DIN specifications. At all measuring points, the tested floor meets the requirements specified in DIN V 18032-2:2001-04 table 1, col. 2 for "area-elastic sports flooring" . [0066] An additional advantage of the sports floor of the invention is the acoustic isolating property. Because the panels 16 actually "float" on an elastic layer 11, there is no direct contact between the "hard" panels on which sportspersons play and the subfloor 1. Moreover, the elastic layer 11 consists of a foam material, such as an agglomerated PU foam, generally having also acoustic isolating properties. Hence, the sports floor of the invention can also be used as an acoustically isolating floor . [0067] While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the present invention . Table 1: Test results according to DIN V 18032-2:2001-04 of the sports floor according to the invention and comparison with the requirements of DIN V 18032-2:2001-04 for area- elastic flooring (source: test certificate L 2793 of 04 June 2007 issued by the Institut fur Sportbodentechnik, Dipl.-Phys. B. Harting VDI, Leipzig, Germany).

Claims

1. A floor for sports facilities comprising:

- an elastic layer,

- a first layer made of a material comprising wood and provided on the elastic layer,

- a second layer made of a material comprising wood and provided on the first layer,

- a reinforcement mesh interposed between the first layer and the second layer and — a floor covering.

2. A panel for use in a floor for sports facilities, the panel comprising:

- a first layer made of a material comprising wood,

- a second layer made of a material comprising wood and - a reinforcement mesh interposed between the first layer and the second layer.

3. The panel according to claim 2, comprising a groove and a tongue for sliding into the groove of an adjacent panel.

4. The panel according to claim 3, wherein the length of a tongue measured at a frontal side of the panel is larger than the length of said tongue measured at the side of the panel remote from said frontal side.

5. The panel according to claim 3 or 4, wherein the groove is formed by two opposing walls having different depths.

6. The floor according to claim 1, comprising a multitude of panels according to any one of the claims 2 to 5.

7. The floor according to claim 1 or 6, wherein the elastic layer is made of a foam material.

8. The floor or the panel according to any one of the preceding claims, comprising adhesive for bonding said reinforcement mesh and said first and second layers .

9. The floor or the panel according to any one of the preceding claims, wherein the reinforcement mesh is at least partially pressed into said first and second layers .

10. The floor or the panel according to any one of the preceding claims, wherein said first and second layers have substantially equal thickness.

11. The floor or the panel according to any one of the preceding claims, wherein the first and second layers are made of plywood.

12. The floor or the panel according to any one of the preceding claims, wherein the reinforcement mesh is made of metal.

13. The floor according to any one of the claims 1 and 6 to 12, having a ball rebound of at least 98%.

14. A use of the floor according to any one of the claims 1 and 6 to 13 as an indoor sports floor.

15. A use of the floor according to any one of the claims 1 and 6 to 13 as an outdoor sports floor.

16. A use of the floor according to any one of the claims 1 and 6 to 13 for acoustic isolation.

17. A method of producing a panel for a floor for sports facilities, wherein the method comprises the steps of: — pressing a reinforcement mesh in between two layers made of a material comprising wood in order to obtain a panel and - providing the panel with a groove and a tongue.

18. The method according to claim 17, wherein in the pressing step a pressure of at least 4 MPa is applied.

19. The method according to claim 17 or 18, wherein the step of providing the panel with a groove and a tongue comprises one or more milling operations.