Square-Edged Laminated Wood Strip or Plank Materials

The present invention relates to square-edged laminated wood strip or plank members particularly useful as wood flooring material and having tongue and groove fittings to assure that top surfaces of adjacent strips of planks will be substantially flush, one against the other.

Various wood flooring materials have been manufactured including laminated wood, wood strip or plank flooring, parquet blocks, and the like. Generally, when a wood flooring material, i.e., strip flooring, is not laminated, a sub-flooring or underlament material first must be applied as a support for the wood flooring material to take into account expansion and contraction as a result of varying temperature and humidity conditions so the wood flooring material does not separate from the layer immediately beneath. Laminated wood flooring materials, on the otherhand, do not substantially expand and contract with changes in temperature and humidity conditions because the veneers or layers of wood are laminated together in a cross-grained fashion to prevent most of the expansion and contraction.

Generally, strip and plan flooring materials of the prior art beveled at their adjacent edges to provide a space between strips or planks at the uppermost surfaces because of inability of the prior art flooring material to provide precise, flush fittings on the uppermost edges of the flooring materials. Adjacent edges of prior art adjacent strips or planks of wood flooring material have been beveled in manufacture so that spaces are left between adjacent strips or planks and, in this manner, slightly different spacings between upper surfaces of adjacent strips or planks are not as noticeable.

In accordance with the present invention, it has been found that by providing laminated wood strip or plank flooring members in which the adjacent edges of adjacent strip or plank members are slightly reverse-beveled, the adjacent edges of adjacent strip or plank members tightly fit together to provide precise, flush contact between adjacent upper surfaces of adjacent strips or planks. The strip or plank wood materials of the present invention are provided in various lengths and various predetermined widths so that the random width and length strip or plank materials can be fitted together to provide a most unexpected and pleasing appearance wherein each adjacent strip or plank member is precisely fitted together and adjacent surface portions are substantially flush, or in contact. In one embodiment of the present invention, the strip or plank is provided as a laminate with the cross-grained adjacent layers or veneers, and substantially only the center veneer is grooved or tongued to provide precise fittings of adjacent strip or plank members having upper surfaces lying in the same plane.

Accordingly, an object of the present invention is to provide wood strip or plank members having tongue and groove fittings for precise, flush fitting of adjacent wood members so that surface portions of adjacent strip or plank members can be fitted together precisely and surface edge portions are substantially flush to prevent uneven spacing between adjacent wood members.

Another object of the present invention is to provide a laminated wood strip or plank member having tongues and grooves therein for precise connection to an adjacent laminated wood strip or plank member wherein an upper or surface veneer of each strip or plank member is back-beveled or reverse-beveled along at least one edge of the strip or plank member. In this manner the upper surface edge of the beveled edge contacts an adjacent strip or plank member for precise and flush fitting at the surface of an adjacent strip or plank member.

Still another object of the present invention is to provide wood strip or plank flooring materials having tongue and groove edges beveled so that adjacent strip or plank members are in contact substantially only at their surfaces.

These and other objects and advantages of the present invention will be apparent from the following detailed description of the invention described with reference to the drawing, wherein.

FIG. 1 is a broken-away elevational view of a floor portion constructed from a plurality of strip or plank wood members manufactured in accordance with the principles of the present invention.

FIG. 2 is an enlarged, broken-away elevational view of a wood strip or plank member of FIG. 1;

FIG. 3 is an enlarged, cross sectional view of the floor portion of FIG. 1 taken along line 3--3 of FIG. 1;

FIG. 4 is an enlarged, cross sectional view of the floor portion, taken along line 4--4 of FIG. 1;

FIG. 5 is a broken-away, enlarged, elevational view of a portion of a wood floor member showing a reverse-beveled, precision-fit edge of the wood strip or plank member of the present invention.

Disclosed is a wood strip or plank member having a tongue member extending centrally outwardly from two edges and a groove formed centrally within another two edges wherein at least one edge is a machined edge including a reverse bevel machined in said edge downwardly and inwardly from a major flat surface of said member to said extending tongue or groove.

Referring now to the drawing, and initially to FIG. 1, there is illustrated a new and improved floor, generally designated by reference numeral 10, comprising a plurality of adjacent wood strip or plank members, generally designated by reference numeral 12, fitted together with tongue and groove fittings.

Referring now to FIGS. 2-4, each of the wood strip or plank members 12 includes an upper major surface 14; a lower major surface 16; a side tongued edge, generally designated by reference numeral 18; a grooved side edge, generally designated by reference numeral 20; a tongued end edge, generally designated by reference numeral 22; and a grooved end edge, generally designated by reference numeral 24.

In accordance with an important feature of the present invention, the side tongued edge 18 includes a precision-fit edge surface 26 machined above a side edge tongue member 28 and the end tongued edge 22 includes a precision-fit end edge surface 30 disposed above the extending end edge tongue member 32. The precision-fit side edge 26 and the precision-fit end edge 30, as shown in FIGS. 3-5, are machined to slope downwardly and inwardly from the upper major surface 14 toward uppermost and innermost edges 34 and 36 of side edge tongue member 28 and end edge tongue member 32, respectively. The precision-fit side edge surface 26 is machined to slope downwardly and inwardly from the upper major surface 14 to the uppermost and innermost edge 34 of the tongue member 28, as shown in FIGS. 3 and 5, at an angle of 2.degree. to 7.degree. from vertical. The precision-fit end edge surface 30 is machined to slope downwardly and inwardly from the upper major surface 14 to the uppermost and innermost edge 36 of tongue member 32, as shown in FIG. 4, at an angle of 2.degree. to 7.degree. from vertical. The precision-fit side and end edges 34 and 36, respectively, allow for precise joining of adjacent strip or plank members 12 by permitting adjacent strip or plank members to come in contact substantially only at their major surfaces 14 along the tongued side edge 18 and the tongued end edge 22, as shown in FIGS. 3 and 4. Accordingly, there will be no measurable space between adjacent strip or plank members 12 where two plank members 12 join in contact at their upper major surfaces 14.

In accordance with another important feature of the present invention, the precision-fit edges 26 and 30 are back-beveled or reverse-beveled at an angle of 2.degree. to 7.degree., preferably 21/2.degree. to 31/2.degree., from vertical. It has been found that a bevel less than about 2.degree. may still include a number of wood imperfections or impreciseness in machining to impede flush contact of the upper major surfaces 14 of adjacent strip or plank members 12. A reverse-bevel greater than about 7.degree. has been found to weaken the upper surface 14 of the strip or plank member 12 at the upper edge of the precision-fit edges 26 and 30 so that the precision fit edges 26 and 30 might be damaged at the upper major surface 14 by being compressed inwardly during handling or installation. To achieve the full advantage of the present invention, the reverse-bevel should be at an angle of 2.degree. to 4.degree. from vertical, preferably 21/2.degree. to 31/2.degree. from vertical.

In accordance with another important embodiment of the present invention, the wood strip or plank members 12 are manufactured from a plurality of layers or veneers of wood: a bottom layer 40, a central layer 42, and an upper layer 44 adhesively secured together at interfaces 46 and 48, as shown in FIG. 2. Adjacent veneers 40 and 42; 42 and 44 are secured together so that the grain direction of bottom layer 40 is at substantially a right angle to the grain direction of central layer 42 and grain direction of top layer 44 also is at substantially a right angle to the grain direction of central layer 42 to achieve greater strength to the wood strip or plank member 12 and to decrease the amount of expansion, contraction and warping ordinarily inherent in wood objects as a result of differences in temperature and humidity conditions.

In accordance with an important feature of the present invention, as shown in FIGS. 2-5, a centerline of the side and end tongue members 28 and 32 and a centerline on side groove 49 and end groove 51 correspond to a centerline of the thickness of the wood strip or plank member 12. To achieve the full advantage of the present invention, the tongues 28 and 32 and the side groove 49 are centrally machined in only the center veneer 42 to ensure that the tongues 28 and 32 fit precisely within the grooves 49 and 51 while maintaining the upper major surfaces 14 on adjacent planks in the same plane when adjacent planks are fitted together. Another advantage of machining the tongues 28 and 32 and the side groove 49 from substantially only the center veneer is that machining can be performed more easily and precisely since the machined portion is grained in a single direction.

In accordance with an important feature of the present invention, end groove 51 is machined in the center veneer 42 as well as the lower veneer 40 and upper veneer 42 to provide an expanded end groove 51 for receiving an end tongue member 32, as shown in FIG. 4, so that end tongue edge 22 and end grooved edge 24 contact substantially only at the upper surfaces 14.

In accordance with another important feature of the present invention, the grooved side edge 20 and the grooved end edge 24 also can be provided with precision-fit edge surfaces 50 and 52, respectively, as shown in FIGS. 3 and 4. The precision-fit edge surfaces 50 and 52 on side grooved edge 20 and end grooved edge 24 are back-beveled or reverse-beveled in the same manner as the precision-fit edges 26 and 30 on side tongued edge 18 and end tongued edge 22. Accordingly, the precision-fit edges 50 and 52 are beveled at an angle of 2.degree. to 7.degree. from vertical downwardly and inwardly, angled from the upper major surface 14 to the grooves 49 and 51, as shown in FIGS. 3 and 4. In this manner, the extending tongue members 28 and 32 will float freely within the grooves 49 and 51, as shown in FIGS. 3 and 4, where adjacent planks are fitted together to contact adjacent precision-fit beveled edges together for contact. Contact is made between adjacent strips or planks 12 substantially only at the upper major surfaces 14.

In accordance with another important feature of the present invention, a side edge surface 54 (FIG. 3) is machined into side edge 18 in the lower veneer 40 from a lowermost edge 55 of the side tongue member 28 to the lower surface 16 of the wood strip or plank member 12 to provide a space "d" between side edge surface 54 in side tongued edge 28 and an adjacent side edge surface 56 (in the side grooved edge 20) disposed below a lowermost edge 57 of the side edge groove 49. Obviously, the side edge surface 56 can be machined as well as, or instead of, side edge surface 54 to provide the spacing "d" between the lower major surfaces 16 of adjacent strip or plank members 12, for example 1/16 inch.

Similarly, and in accordance with another important feature of the present invention, an end edge surface 58 is machined into end edge 22 (FIG. 4) in the lower veneer 40 from a lowermost edge 60 of the end tongue member 32 to the lower surface 16 of the wood strip or plank member 12 to provide a space "D", for example 1/8", between end edge surface 58 in end tongued edge 22 and an adjacent end edge surface 62 (in the end grooved surface 24) disposed below a lowermost edge 64 of the end edge groove 51. Again, end edge surface 62 can be machined as well as, or instead of, end edge surface 58 to provide the spacing "D" between the lower major surfaces 16 of adjacent strip or plank members 12.

Generally, the strip or wood strip or plank members of the present invention are laminated to a thickness of at least about 3/8 inch and preferably at least 1/2 inch so that the upper major surface 14 can be sanded and refinished as desired.

While the above described invention has been described with respect to specific embodiments, certain modifications would be obvious to those skilled in the art and are intended to be included within the scope hereof .