A paneling board with a wooden sight surface, and method of manufacturing same

DESCRIPTION

This invention relates to a paneling board with a wooden sight surface, and a method of manufacturing same.

Boards of the above kind are widely employed in the building industry for wall paneling.

Such boards generally comprise a prime surface provided by a veneer of quality wood and intended to be in sight in the installed condition of the board, which veneer is glued to a support ply usually provided by some low-quality wood agglomerate, e.g. -the agglomerate known as shake.

These composite boards afford the undisputed advantage of a significantly lower cost per unit of paneled area than conventional all-wood boards. On the other hand, they can only be used for wall paneling and are unsuited to flooring applications, for example.

In the last-mentioned application, it is customary to fabricate floorings by laying all-wood strips side-by-side over a floor substrate. Such floorings are best known by the term "parquet".

In view of that parquets are expected to provide adequate structural strength as well as tread resistance, the thickness of the strips used for their construction is bound to be comparatively high, at least when compared with that of the thin veneering of the boards used for wall paneling.

In addition to their high cost, parquet floorings have some well-recognized disadvantages in that they are relatively difficult to install, require the availability of qualified personnel, and that the finished flooring is apt to set over time because shrinkage, distortion, or even breakaway and

partial buckling of the parquet off the substrate are likely to occur later according to the degree of seasoning and the moisture content of the installed wooden strips.

In order to overcome within limits the last-named disadvantage, which originates basically from increased moisture and consequent swelling of the strips out of their as-installed condition, some precautions must be taken such as that of providing a thoroughly waterproofed substrate, and that of only installing the flooring after the substrate has been thoroughly dried. But this cannot rule out the possibility that any liquids spilled onto the flooring after its installation may get through the unavoidable gaps between adjacent strips and wet the substrate; this wetting, if not the liquid itself, would then be taken in gradually by the strips through their undersides next to the substrate to result in swelled strips and the above-mentioned unfavorable situations.

The underlying problem of this invention is to provide a board which is designed for use in panelings of any kinds, and particularly in floorings, without incurring the problems with which the prior art referred to is beset.

This technical problem is solved according to the invention by a paneling board with a wooden sight surface being characterised in that it comprises a first ply including at least one wooden strip bonded to a second, supporting ply made of a plastics material.

This board construction, owing to a reduced consumption of valuable material (wood), can be less expensive for the same area of paneled surface than traditional parquet floorings, while providing unaltered strength features and being

in particular unaffected by moisture from the floor substrate.

Advantageously, said first ply comprises a plurality of wooden strips laid side-by-side, and in a further aspect, said supporting ply comprises a foam resin. This configuration can provide boards in varying sizes without the boards being liable to become distorted, particularly after their installation, and add to the above-noted strength and imperviousness, improved sound-deafening and thermal insulating features for the board.

As an added advantage, said strips forming the first ply are so arranged as to define corresponding gaps between adjacent strips, said supporting ply surfacing at least in part through said gaps.

This construction affords further improvement of the board imperviousness to liquids spilled onto the wooden sight surface.

The features and advantages of the invention w ll become more clearly apparent from the following detailed description of a preferred embodiment thereof, given by way of illustration and not of limitation, with reference to the accompanying drawings, where:

Figure 1 is a perspective top view of a board embodying this invention,

Figure 2 is a fragmentary perspective bottom view of the board shown in Figure 1,

Figure 3 shows the board of the preceding figures in side elevation, and

Figure 4 is a fragmentary sectional representation of one step of the manufacturing process of the board shown in the preceding figures.

Figure 5 is a perspective view of another embodiment of this invention partially in cross section.

Shown generally at 1 in the drawing figures is a paneling

board with a wooden top or sight surface embodying this invention.

The board 1 comprises a first ply, generally shown at 2, which is made up of plural wooden strips 3 laid side-by-side, and a second ply also referred to hereinafter as the supporting ply and being generally indicated at 4, which is made of foam plastics, preferably a closed-cell rigid polyurethane plastics foam. A substantially flat surface 5 is defined on the first ply 2 which is to remain in full sight with the board in the installed condition.

The dimensional ratio of the thickness (as measured perpendicularly to the surface 5) of the first ply to that of the second lies preferably within the range of 1:1 to 1:20. As an example, the first ply may have a thickness dimension in the 2 to 6 mm range, and the thickness of the second ply may be in the 5 to 30 mm range. As a preferred material for the second ply, mention can be made of a polyurethane resin

(TM) sold by Elastogran Italiana under the trade name of ELASTODUR

Between adjacent strips 3 there are defined corresponding gaps 6 due basically to uneveness of the strip geometry, which are responsible for imperfect mating of the same. The gaps 6 are filled with material from the second ply 4, which rises to the Level of the surface 5.

In addition, said material will provide a film enveloping the whole periphery of the board 1 or at least major sections thereof.

Formed in the underside of the board 1, remote from the surface 5, are recesses 7 at pitch distances from one another. Said recesses 7 result from the board manufacturing method

SUB TITUTE HE

but also serve to lighten the board construction and facilitate its installation by cementing.

To fabricate the board 1, the strips 3 are first laid into a mold 10 which is closed by a detachable lid 11, thereby said strips will rest side-by-side on a bottom wall 12 of the mold 10.

Said wall 12 is moderately arcuate (the curvature being shown exaggerated in Figure 4 for clarity of illustration) with its convex side facing the lid 11. A plurality of pips 13 are provided on the lid which are effective to produce the recesses 7 in the second ply 4 as explained hereinafter. The pips 13 are arranged to urge the strips 3 against the wall 12 and force them into a bent configuration with the convex side toward the second ply 4. They provide a means of holding the strips 3 pressed against the mold bottom wall 12; any equivalent means may be used for the same purpose, such as vacuum-forming pneumatic arrangements drawing through the wall 12 to urge the strips thereagainst, or some different pressure members between the strips and the mold lid 11.

After applying the lid 11, or just before its application, a polyurethane resin in a flowable state is injected or anyhow introduced into the mold 10 which can be later foamed and cured. The resin will flow through the gaps 6 usually left, at least partway between adjacent strips 3, and up across the walls of the mold 10 to envelop the periphery of the board 1 being formed.

On hardening and curing, the polyurethane resin will provide the second ply 4.

On being shaken out of the mold 10, the board undergoes

E SHEET

elastic recover and will take up the deformation imposed bra it by the curvature of the wall 12.

If desired, the surface 5 of the board 1 may be smoothed prior to its installation and given a coat of varn.ish as indicated at 14 in Figure 3. Alternatively, the board could be first installed as supplied in an already excellent state of finish, and then smoothed and/or varnished.

In Figure 5 there is shown another embodiment of this invention generally indicated at 101; similar particulars are indicated by the same reference numerals as in the previous example.

The board 101 is substantially identical to the board 1 of the first example except for the provision of reinforcing steel bars 102, omega shaped in cross section, extending transversely with respect to the general longitudinal dimension of the wood strips 3. Each bar 102 is provided with two wings 102a,b facing the lower surface of the wood strips 3. Projecting from each wing is a plurality of nail members 103 subjected to penetrate into the wood of the strips 3 for holding fast the wood and the bars to each other. Distortion of the board 101 is thereby prevented in any condition.

The bars 102 also constitute pressure members for holding the strips 3 pressed against the mould bottom wall 12 while the board is being manufactured.

Among the main advantages afforded by this invention mention can be made of that the boards provided are truly waterproof also and particularly as regards their surface in contact with the floor substrate. This enables installation of the boards with no risk of any moisture in the substrate causing distortions or damage to the installed flooring.

Further advantages come from the lightweight, dimensional stability, low manufacturing cost, and insulative properties of the flooring provided.