Background of the invention

The invention relates to a wall panel which comprises a frame structure and a first board and a second board attached to it, whereby there is an insulation space between the first board and the second board. More specifically, the inven tion relates to a wall panel according to the preamble of accompanying claim 1. The wall panel is suitable for use in house construction. The invention also relates to a wall structure which comprises two similar wall panels stacked on top of each other. A wall panel of said kind is know from patent specification

GB2490304A. The suitability of this known wall panel to provide sturdy and tall vertical wall structures for e.g. multi-storey houses is poor.

Brief description of the invention

The object of the invention is to provide a novel multipurpose wall panel which enables producing sturdy tall walls in house construction by stacking several wall panels according to the invention on top of each other. The walls can be inte rior or exterior walls. In order to achieve this object, the wall panel according to the invention is characterized by what is disclosed in the characterizing part of the attached claim 1. The wall panel according to the invention comprises a set of adjacent elongated support structures to which are attached opposite first and second wall- panel boards as well as first and second partition boards offset such that top ends of the support structures form a tongue structure to the first end (e.g. top end) of the wall panel, and the bottom ends of the first partition boards form a groove structure with the bottom end of the first boards of the wall panel (also the bottom ends of the second partition boards and the bottom end of the second board of the wall panel form a groove structure) to the second end of the wall panel, which is opposite in relation to the first end of the wall panel, which tongue structure and groove structure enable forming a tongue-and-groove joint with two similar wall panels when they are stacked on top of each other for attaching the wall panels together. Most preferably said structures form in the wall panel a set of separate first additional spaces between the first partition boards and the first board of the wall panel and between the second partition boards and the second board of the wall panel, which additional spaces can have various functions depending on the use and purpose of the wall panel. The first and second additional spaces function as sound and heat insulation and can form ventilation channels in the height direc tion of the wall panel. An essential characteristic of the wall panel according to the invention is that there are openings at the upper ends of the elongated support structures and there are openings at the bottom ends of the elongated partition boards and there are openings at the bottom ends of the first board and the second board for receiving fastening dowels, with the help of which fastening dowels two wall panels set on top of each other can be locked together at the point of the tongue-and-groove joint such that the fastening dowels go through the openings at the bottom ends of the elongated partition boards of the upper wall panel and through the openings at the top ends of the elongated support structures of the lower wall panel. Said openings and fastening dowels enable the stacking of two sim ilar wall panels and their easy attachment together on top of each other such that the result is a joint between the wall panels which joint is very sturdy and prevents external forces or loads from transferring wall panels set on top of each other in relation to each other in the direction of the planes of the wall panels, including transfers in the vertical direction, and also decreasing the so-called hinge effect i.e. that the wall panels set on top of each other fall due to lateral forces at the point of the tongue-and-groove joint and settled in a position in which the wall panels are not accurately parallel.

Preferably the top ends of the support structures are tapering upwards i.e. they contain bevels. The bevels considerably facilitate the mounting of the wall panels on top of each other, because it is possible to describe the tongue-and- groove joint between the wall panels stack on top of each other as tolerance-free.

Preferably, the frame structure of the wall panel is of wood or of mate rial containing wood. Preferably, the first additional spaces of the wall panel contain sand.

The sand provides the wall panel with a good damping capacity against structure- borne sounds, such as against knocking caused by impacts.

Preferred embodiments of the invention are disclosed in the attached dependent claims. The great advantage of the wall panel according to the invention is that it enables producing very sturdy vertical walls and wall structures by installing two or several wall panels according to the invention on top of each other. The wall structures also endure well lateral forces which can be caused by wind loads. In the wall panels set on top of each other, the elongated support structures are in line without tolerance and the partition boards are in line without tolerance. Together, the support structures and partition boards form vertical structures which can be loaded with very high forces in the vertical direction in order to construct even a multi-storey house. The first and the second boards of the wall panels are also in line preferably without tolerance, which further increases the load-bearing capac ity of the wall panels in the vertical direction. An advantage of the wall panels is also that the separate additional spaces in the wall panel, which form vertical chan nels, can be utilized for many kinds of use depending on the use of the wall panel: sound insulation (structure-borne sounds in addition to air sounds), electric wir ing, installation of water pipes etc. The wall structure according to the invention is sturdy and easy to build up from the wall panels according to the invention.

Brief description of the drawings

The invention will now be described in more detail by means of a pre ferred embodiment thereof and with reference to the accompanying drawing, in which

Figure 1 shows a perspective view of a wall panel according to the in vention,

Figure 2 illustrates a top view of the wall panel of Figure 1,

Figure 3 illustrates the attaching of two wall panels according to the in vention to each other,

Figure 4 shows a tongue-and-groove joint of two wall panels according to the invention set on top of each other,

Figures 5 and 6 illustrate the manufacture of a wall panel according to the invention,

Figure 7 shows an elongated support structure in the wall panel of Fig ure 1, and

Figure 8 shows an alternative support structure for Figure 7.

Detailed description of the invention

Figure 1 shows a rectangular wall panel according to the invention. Fig ure 2 illustrates a top view of the wall panel of Figure 1. The height of the wall panel if 2.5-4 m, its width 2-5 m and its thickness LI (see Figure 2) 100-800 mm. The height of the wall panel is preferably such that a wall equivalent to the height of a room in a multi-storey house can be provided with one panel.

The wall panel comprises a frame structure 7 and a first board 8 being supported by it and a second board 9. Face surfaces of the boards 8, 9 are desig- nated as 1 and 2, respectively (see Figures 1 and 2). The boards 8, 9 are fastened to vertical elongated support structures 10 of the frame structure 7, of which sup port structures there are several arranged adjacently at a distance L2 from each other. The number of the support structures 10 is 5 to 20 depending on the width of the wall panel. The distance L2 is 200-700 mm. The frame structure 7 also in- eludes a set of elongated vertical partition boards 13a, 13b which are fastened to the support structures 10. The thickness of the partition boards 13a, 13b can be 10-70 mm depending on the purpose of use of the wall panel. The interior of the wall panel comprises an insulation space 14 which preferably contains polyure thane or polystyrene. The polyurethane and the polystyrene operate as heat and sound insulation as well as make the wall panel sturdier. The width i.e. thickness L4 of the insulation space 14 is 100-350 mm.

The construction of the support structure 10 is shown in Figure 7. The support structure 10 comprises a plank-like first post 10a and a plank-like second post 10b which is parallel with the first post. The posts 10a, 10b are joined by a set of connecting pieces 10c, whereby the support structure 10 is ladder-like. The cross section of the plank-like posts 10a, 10b is a rectangle. Due to its ladder-like structure, the support structure 10 is light. The number of the connecting pieces 10c in the support structure 10 is preferably 3to 7. The height (length) L3 of the support structure 10 equals the height of the wall panel. In Figure 7, number 11 designates a first mounting surface onto which the first board 8 of the wall panel is attached, cf. Figures 1 and 2. The post 10b includes an equivalent mounting surface onto which the second board 9 is attached, cf. Figures 1 and 2 (designation 12 in Figure 2 shows said second mounting surface). The first mounting surface 11 and the second mounting surface 12 are formed of the end surfaces pointing outwards of the plank-like posts 10a, 10b. The boards 8, 9 are attached onto the mounting surfaces 11, 12 with screws, nails or glue.

In Figures 1 and 2, the first and the second partition boards 13a, 13b are set between the support structures 10 preferably without tolerance. The length L3 of the partition boards 13a, 13b equals the height of the wall panel. The partition boards 13a, 13b are attached e.g. with nails onto the inner surfaces of the posts 10a, 10b of the support structure 10 which inner surfaces form support surfaces for the partition boards. The attachment of the partition boards 13a, 13b onto the inner surfaces of the posts 10a, 10b can alternatively or additionally implemented with glue. Figure 2 shows best that the partition boards 13a, 13b form in the wall structure a set of separate first additional spaces 15a and a set of separate second additional spaces 15b. In more detail, the first additional spaces 15a are between the first board 8 and the first partition boards 13a and are limited by the first board 8, the first partition boards 13a and the support structures 10. Equivalently, the second additional spaces 15b are between the second board 9 and the second par- tition boards 13b and are limited by the second board 9, the second partition boards 13b and the support structures 10. If the wall panel is an exterior wall panel and the wall 9 is an exterior wall, additional spaces 15b can be air ducts which op erate as ventilation ducts or ventilation gaps of the wall panel. The additional spaces 15a can - irrespective of the wall panel being an exterior wall panel or an interior wall panel - filled partially or totally with sand which provides the wall panel a good sound attenuation against impact noises. The grain size of the sand is preferably 0-4 mm. The additional spaces 15a and/or 15b can alternatively or ad ditionally operate as channels for electric wires or pipes. If the sound insulation of the wall panel is particularly important, both the additional spaces 15a and the ad- ditional spaces 15b contain sand. Such a wall structure can be used between room spaces as the so-called separation wall. The width (thickness) of the additional spaces 15a, 15b i.e. the distance of the boards 8, 9 from the partition boards 15a, 15b is 30-70 mm.

Figures 1, 3 and 4 show that the elongated support structures 10 are offset in relation to the boards 8 and 9 such that the top ends 16 of the support structures 10 are arranged above the top ends 17 and 21 of the first board 8 and the second board 9, respectively, and above the top ends 18a and 18b of the first and the second partition boards 13a and 13b, respectively, in order to provide a tongue structure at the first end 3 of the wall panel (the top end of the wall panel in the Figures), whereby the bottom ends 19 of the elongated support structures 10 are arranged above the bottom end 20 of the first board 8 and the bottom end of the second board 9 and above the bottom ends 22a and 22b of the first and the second partition boards 13a and 13b, respectively, whereby the bottom ends 22a and 22b of the first and the second partition boards 13a and 13b, respectively, and the bottom ends 20 of the first and the second board 8 and 9, respectively, form a groove structure at the second end 4 of the wall panel (the bottom end of the wall panel in the Figures), which tongue structure and groove structure enable the forming of a tongue-and-groove joint between two similar wall panels when they are set on top of each other in accordance with Figure 4. The described wall panels provide a tongue-and-groove joint which comprises two tongues and two grooves working in co-operation with the tongues, whereby the tongue-and-groove joint can be called a double tongue-and-groove joint. Figure 3 illustrates the setting of the wall panels on top of each other for attaching them together to provide the tongue-and-groove joint shown in Figure 4. The top ends 16 of the support struc tures 10 are tapering upwards i.e. they are bevelled, whereby they are easily di- rected to the groove structure at the bottom end of the upper wall panel. The bevels greatly facilitate attaching the wall panels together, because the formed tongue structure is in practice tolerance-free, which without bevels would necessitate the extremely accurate aligning of the wall panels being set on top of each other before the ends of the wall panels can be attached. It can be considered that alternatively or additionally the bottom ends of the partition boards 13a, 13b are also bevelled (not shown in Figures) in order to facilitate providing the tongue-and-groove joint or that only the bottom ends of the partition boards are bevelled, whereby the top ends 16 of the support structures 10 are left unbevelled. However, it is much more preferable from the viewpoint of the manufacture of the wall panel that the top ends 16 of the support structures 10 are bevelled than that the bottom ends 13a, 13b of the partition boards are bevelled.

In Figure 4, the components of the wall panel on the top are designated with the same numbers as the components of the wall panel on the bottom and the components of the wall panel shown in Figures 1 and 2. In the tongue-and-groove joint shown in Figure 4, the bottom end 4’ of the upper wall panel is supported on the top end 3 of the lower wall panel such that the bottom end 19’ of the support structure 10’ of the upper wall panel is supported on the top end 16 of the support structure 10 of the lower wall panel. The support is tolerance-free in the vertical direction and also in the lateral direction. The bot- tom ends 22a’, 22b’ of the partition boards 13a’ and 13b’ of the upper wall panel are supported by the top ends 18a, 18b of the partition boards 13a and 13b of the lower wall panel. Due to the shown tolerance-free support of the support struc tures 10’ and 10 and the partition boards 13a’, 13b’ and 13a, 13b, the wall struc tures endure well high vertical loads. This is important when setting several wall panels on top of each other when constructing a multi-storey house. Preferably, the bottom ends 20’ of the boards 8’, 9’ of the upper wall panel are supported on the top ends 17, 21 of the boards 8, 9 of the lower wall panel, because this increases the rigidity and load-bearing capability of the wall panels.

In Figure 4, number 23 designates openings at the top ends 16 of the support structure 10. When the upper wall panel is set on top of the lower wall panel and the tongue-and-groove joint formed, the fastening dowels 25 are pushed into the openings 23, whereby the tongue-and-groove joint is locked. At the bottom ends of the partition boards 13a’, 13b’ are equivalent openings 26’ into which said fastening dowels 25 go, cf. openings 26 and 24, respectively, in Figure 1. The diam eter of the openings 23, 24, 26 and the fastening dowels 25 is 20-30 mm. The num ber of the openings 23, 24, 26 may vary. The fastening dowels 25 are preferably of wood. When the fastening dowels 25 are pushed through either board 8 or 9, as it is recommended when forming the joint between two wall panels, there should also be openings at the top and/or bottom ends of the boards 8 and/or 9, cf. the openings 28 at the bottom end of the board 8 in Figure 1.

Figures 5 and 6 illustrate the manufacturing of a wall panel. First, a set of support structures 10 are set adjacently (Figures 5 and 6 show six support struc tures adjacently in line), after which, the support structures are attached to each other by the partition boards 13b. Preferably, the partition boards 13b set against the connecting pieces 10c of the support structures 10 thus attaching to the latter e.g. by a nail joint. Then, the partition boards 13a are attached to the support struc tures 10 (not shown in Figure 6), after which, the boards 8 and 9 and are fastened onto the mounting surface of the support structures 10.

Figure 8 shows an alternative and possible support structure for the support structure 10 of Figure 7. The support structure of Figure 8 is lighter that the support structure of Figure 7, but its strength does not nearly equal the strength of the support structure of Figure 7; furthermore, attaching the connect ing pieces to the support structure of Figure 8 is tricky, because the support struc ture of Figure 7 does not include a large support surface for the attachment of the connecting pieces.

The support structure 10 of the wall panel is preferably of wood. The partition boards 13a, 13b are of OSB board, plywood, fibreboard, veneer plate or plasterboard.

In the following, a list is presented to explain the meaning of the desig nations used for describing the invention.

1 first face surface of wall panel

2 second face surface of wall panel

3 first end of wall panel

4 second end of wall panel

5 first side of wall panel

6 second side of wall panel 7 frame structure of wall panel 8 first board of wall panel

9 second board of wall panel

10 elongated support structure 10a plank-like first post 10b plank-like second post 10c connecting piece 11 first mounting surface of support structure 10 12 second mounting surface of support structure 10 13a first partition board 13b second partition board 14 insulation space 15a first additional spaces 15b second additional spaces 16 top end of support structure 10 17 top end of first board 8 18a top end of first partition board 13a 18b top end of second partition board 13b

19 bottom end of support structure 10

20 bottom end of first board 8 21 top end of second board 9 22a bottom end of first partition board 13a 22b bottom end of second partition board 13b

23 opening at top end of support structure 10

24 opening at bottom end of second partition board 13b

25 fastening dowel

26 openings at bottom ends of partition boards 13a 28 openings at bottom end of board 9 LI distance (thickness of wall panel) L2 distance (mutual distance between support structures 10) L3 distance (length of support structure 10), height of first and second board, length of partition boards 13a, 15 L4 thickness of insulation space 14

In the above, the invention is only described by means of an example, wherefore it should be noted that the details of the invention may be implemented in various ways within the scope of the attached claims. Hence for example, the support structures 10 do not have to be ladder-like structures, even though ladder like structures are particularly preferable due to their high strength in relation to their weight. Instead of a wooden ladder-like support structure, i can be considered that a metal U profile can form the support structure. The number and dimensions of the support structures 10 included in the wall panel and also other components can vary depending on the intended use.