The present invention relates in general to stair noses and other moldings made from luxury vinyl plank flooring, and to methods, tools, and machines for forming the stair noses and other moldings from luxury vinyl plank flooring.
Flooring manufacturers and installers have tried many different methods for providing custom stair noses that match the surrounding floor. Typical methods involve cutting off the existing stair nose and then installing a replacement stair nose closely matching the floor being installed, as shown in
One problem that occurs with replacing stair treads along with the rest of the adjacent flooring is matching the wood grain pattern and color. Even when the exact same type of wood and finish is used for both nose plank 20 and flooring plank 30, the color and pattern are usually off. All the floor planks 30 being used are usually made together at the same factory at the same time to match practically exactly. However, nose planks 20 are typically formed separately and, while they may match flooring planks 30 closely, will almost always have a noticeable difference in color and pattern due to being manufactured at a different time or even a different factory.
Luxury vinyl plank (LVP) flooring is a modern type of flooring that is susceptible to the problems of color matching stair nosing and other molding.
The desired design for the flooring is printed on image layer 56 and then attached to core 52. Image layer 56 can be a vinyl sheet or another printable substrate. Clearcoat layer 58 typically consists of anywhere from 1 to 100 layers of clearcoat or more. Usually between 10 and 25 layers of clearcoat are used. Clearcoat layer 58 protects the printed image layer 56, and plank 50 as a whole, from wear.
Luxury vinyl plank flooring is typically formed with connectors 60 around the perimeter of planks 50 so that individual planks can be clicked or snapped together with other adjacent planks to easily form a floor with proper alignment and a seamless transition between planks.
While LVP flooring makes installing a beautiful floor easier, LVP does not eliminate the problems of matching stair nosing to the surrounding flooring. The closest matching hardwood nosing is usually used even though the vinyl planks are printed. Achieving an exact match is very difficult. Therefore, a need exists for an improved stair nose, as well as other types of molding, that matches LVP flooring planks.
The present invention is described in one or more embodiments in the following description with reference to the figures, in which like numerals represent the same or similar elements. While the invention is described in terms of the best mode for achieving the invention's objectives, it will be appreciated by those skilled in the art that it is intended to cover alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims and their equivalents as supported by the following disclosure and drawings.
One solution to providing stair noses that match luxury vinyl plank (LVP) flooring is to make the stair noses out of the same LVP planks that are being installed for the flooring. Using the same planks for both stair noses and the rest of the flooring means that the stair nose planks are manufactured at the same plant and under the same conditions as the rest of the flooring planks. The issues in the prior art with slight variations in manufacturing conditions resulting in slightly off colors and patterns are eliminated because stair nosing and floor planks are manufactured together.
Making a stair nose out of LVP flooring involves cutting grooves into a floor plank and then folding the plank at the grooves into a stair nose shape.
Two grooves 110a and 110b are formed into bottom surface 102, but not completely through plank 100 to top surface 104.
In the illustrated embodiment, plank 100 is 8 millimeters (mm) thick, and groove 110 is formed to a depth of 7 and ⅓ mm, leaving a thin flat flexible portion 120 between horizontal surface 112 and top surface 104 with a thickness of ⅔ mm. A thickness of ½ mm is left as flexible portion 120 in other embodiments. The depth of groove 110 can be formed as close to image layer 56 as possible without damaging the image layer. Ideally core 52 would be completely removed but doing so without damaging printed layer 56 can be a challenge. Accordingly, a thin portion of core 52 is typically left under horizontal surface 112 by design. Core material 52 is flexible enough that a thin layer remaining still allows plank 100 to be folded at groove 110. In one embodiment, groove 110 is formed to leave a fixed thickness of plank 100 in flexible portion 120 so that the remaining thickness of core 52 will depend on the total thickness of image layer 56 and clearcoat layers 58.
The width of horizontal surface 112, and therefore the width of flexible portion 120 and the distance between vertical surfaces 114, is 3.2 mm. Vertical surfaces 114 have a height of 1.6 mm, and diagonal surfaces 116 each extends off at a 45-degree angle from a respective vertical surface to bottom surface 102. At bottom surface 102, diagonal surfaces 114 are approximately 0.5772 inches or 14.66 mm apart. Horizontal surface 112, vertical surfaces 114, and diagonal surfaces 116 all extend in the same profile shape for the entire length of plank 100. Any of the above measurements can be customized as needed for different plank types, compositions, sizes, etc. to ensure that diagonal surfaces 116 make proper contact when folded.
Grooves 110 with a flat horizontal surface 112 at the bottom of the grooves leaves a flat flexible portion 120 of plank 100 between horizontal surface 112 and the plank's top surface 104. Flexible portion 120 has a relatively uniform thickness for a significant width, which allows plank 100 to bend uniformly along the entire width of horizontal surface 112 when the plank is folded. Diagonal surfaces 116 could meet at a point at the bottom of the groove, but bending of plank 100 would occur over a much thinner area of plank 100 and risk tearing of image layer 56. For planks that are not as flexible, horizontal surface 112 can be made wider, allowing the plank to bend across a wider arc, or portion 120 can be made thinner to flex easier.
Each diagonal surface 116 is at a 45-degree angle so that the angle between the two diagonal surfaces is 90 degrees. When plank 100 is bent across groove 110, diagonal surfaces 116 contact each other when the plank is flexed to the same angle as exists between the diagonal surfaces. For a 90-degree bend in plank 100, diagonal surfaces 116 should make a 90-degree angle when formed. A non-symmetrical groove could be formed with, e.g., one diagonal surface 116 at a 30-degree angle and the other at a 60-degree angle, and the diagonal surfaces would still meet when plank 100 is bent to 90 degrees. Plank 100 can be folded or bent at non-right angles by varying the total angle between diagonal surfaces 116.
The height of vertical surfaces 114 in combination with the width of horizontal surface 112 controls how diagonal surfaces 116 meet when plank 100 is folded. The ideal is to have diagonal surfaces 116 lie flat on each other perfectly aligned so that the entire area of each diagonal surface is contacted by the other diagonal surface. If vertical surfaces 114 are made too short, the top edges of diagonal surfaces 116 will meet first and the diagonal surfaces will not fully touch. If vertical surfaces 114 are made too tall, the bottom edges of diagonal surfaces 116 will meet first and make full contact difficult. The above listed dimensions were found through trial and error to be optimal for most LVP flooring on the market today. However, if diagonal surfaces 116 are not meeting each other properly in practice, some dimensional adjustment might help.
A gap between horizontal surface 112 and vertical surfaces 114 is shaped like an isosceles right triangle with an outwardly curved hypotenuse. The gap should be filled with adhesive 130 with as few voids as possible to maximize hold of the plank 100 folds. Thorough application of adhesive 130 can be confirmed by viewing a bead formed by the adhesive being squeezed out of groove 110 during folding. If the bead of adhesive 130 is continuous along the length of plank 100 then the gap between horizontal surface 112 and vertical surfaces 114 is likely to be filled with adhesive. Small breaks in the bead of adhesive 130 are likely fine, but long breaks in the bead may indicate an adhesive void in groove 110 at that location.
Bending and gluing both grooves 110 to 90-degree angles completes the transformation of plank 100 into a stair nose 150. Stair nose 150 is ready to be put into service on a stair step. To install stair nose 150, glue or adhesive 152 is first applied to bottom surface 102 as shown in
Adhesive 152 is applied to bottom surface 102 in sufficient quantity to adhere stair nose 150 to the underlying stair tread 12. In addition, a bead 154 of adhesive 152 is applied over the folded groove 110b so that, when stair nose 150 is installed on a stair step as shown in
With stair nose 150 installed, additional planks 100 can be laid next to the stair nose to continue the rest of the floor as shown in
Flexible portion 184 is similar to flexible portion 120 in groove 110, and is formed with a thickness of about ⅔ mm. Some core 52 remains in some embodiments. The width of flexible portion 184 is two to three times greater than the width of flexible portion 120 because the square cut in
With blades 200a-200c ground down to the desired shapes, the three blades are combined to operate as a single blade on a table saw.
Combined blade 210 has the appropriate profile to cut groove 110 due to being cut to the proper dimensions. However, the individual blades 200 will eventually need to be sharpened. Keeping the proper saw blade profile after sharpening can be a challenge. The profile of combined blade 210 can be adjusted by adding shims or washers 212 between the individual blades 200a-200c as shown in
As an alternative,
To create grooves using the above blades, the blades are installed into a table saw and planks 100 are run across the table saw. The cutting process begins by optionally heating up planks 100. A stack or pallet of planks can be placed in a heated area or container prior to having grooves cut. A bread proofing box can be used for instance. Heating planks 100 prior to cutting grooves makes clearcoat layers 58 more flexible, thus helping reduce the likelihood that the clearcoat layers will chip during the sawing process. Planks 100 are heated to 98 degrees Fahrenheit (° F.) in one embodiment.
A heating element 280 is disposed under slots 276. Any type of heating element is usable, e.g., a gas burner or a resistive electric heater. The heating element can be as simple as a food warmer lamp. Slots 276 are positioned directly under grooves 110 with a portion 282 of table 271 limits heat being directly applied to the portion of plank 100 between the grooves. Applying heat specifically to grooves 110 and limiting the application of heat to other areas of planks 100 helps the planks fold at the grooves without bending or being misshapen in other areas. The thinner areas of plank 100 at grooves 110 heat up more quickly than the areas remaining at full thickness, so heating just the grooves is relatively easy. A target temperature of 125° F. is sufficient for folding planks 100 and will keep the planks under most manufacturers' recommended maximum temperature.
Next, adhesive 130 is disposed into grooves 110. Adhesive 130 is a two-part adhesive in one embodiment. The two-part adhesive involves first spraying an activator into grooves 110 and then dispensing in a bead of glue. Cyanoacrylate (CA) glue is one suitable adhesive. Once the CA glue is applied onto the activator in grooves 110, the worker has about 10 seconds to fold plank 100 into the desired shape for stair nose 150 before the glue becomes too hard to work.
Another embodiment uses a single-stage hot urethane or polyurethane (PUR) adhesive. The PUR adhesive is dispensed into grooves 110 at a high enough temperature, typically 230° F., that a separate heating element 280 is not required. Using a PUR adhesive to heat the area around grooves 110 provides sufficient heat without needing heating elements 280 and keeps heat localized to the grooves without requiring slots 276. Adhesive 130 can be dispensed from a bottle, fed in from a large tank using a hose and nozzle, or applied using any other suitable mechanism.
Once adhesive 130 is disposed in grooves 110, plank 100 is folded up into two 90-degree angles and placed between table 271 and clamp bar 292 as shown in
One of the swing arms 294 has a switch 296 extending out past clamp bar 292 that a worker can press with his or her hip to move the clamp bar away from table 271 and allow insertion of a folded-up plank 100. Clamp bar 292 is spring loaded with spring 297 so that when the worker stops pressing on switch 296 the clamp bar compresses plank 100 between the clamp bar and table 271 to hold the 90-degree folds without additional input from the worker. In other embodiments, springs 297 are used at both ends of clamp bar 292.
The folding of plank 100 will squeeze some adhesive 130 out to form a visible bead inside stair nose 150. For two-part adhesives, an addition spray of activator can be applied after folding to ensure that the bead hardens. The activator helps adhesive 130 get a better grip on the inside of the folds and reduces the amount that the wet adhesive runs on the inner surfaces of stair nose 150. 20-30 seconds of drying is typically sufficient for adhesive 130, and then the completed stair nose 150 can be stacked for packaging and shipment to the customer.
In some embodiments, heating, applying adhesive, folding, and holding while the adhesive dries can all be automated. A robot can apply adhesive before running a plank 100 through a folding machine, such as one that might be used for roll forming sheet metal into channel beams. The entire process from loading a plank 100, cutting grooves 110 or 180, to gluing the folds in place can be automated by connecting robots in an assembly line. Robots can be configured to take a pile of new planks 100 and convert the planks into a stack of stair nosings 150 without human intervention.
In addition to stair nosing, other types of molding can be formed by cutting and folding luxury vinyl plank flooring. Any type of molding can be formed, and each has the advantage of matching the surrounding flooring due to being formed from one of the same planks that was used for the flooring.
To form strip 300 into a T molding, the strip is cut or shaved down to the profile shown in
Platforms 304 surround middle portion 302 on both sides and have bottom surface 102 shaved down to about 20-25% of the total plank 100 thickness, i.e., about 75-80% of the plank material is removed within the footprints of platforms 304. In one embodiment, a thickness of platforms 304 is about 1 mm and a width of each platform 304 is between ¼ and ½ inch. Platforms 304 will be the portion of the T molding that sits on the surrounding flooring, while middle 302 will be the portion of the T molding that sits between the surrounding flooring.
Flaps 306 have bottom surface 102 of strip 300 shaved down to between ½ mm and ⅔ mm thickness. The exact thicknesses of flaps 306 and platforms 304 are not critical, but the flaps should be thin enough to be folded under the platforms as shown in
Platforms 304 and flaps 306 can be cut or shaved down using a single saw with a profile matching the desired shape, as done above for grooves 110 and 180. One platform 304 and flap 306 could be cut followed by the platform and flap on the other side of middle 302. Heat can be applied as with grooves 110 and 180 to reduce the likelihood of damaging the clearcoat layers. In another embodiment, a custom planer blade is designed to cut platforms 304 and flaps 306. Any suitable tool or machine can be used to cut a plank 100 into the shape of
Once plank 100 is cut into the shape shown in
Strip 300 with flaps 306 folded under as shown in
Whatever the case, T molding 310 covers up the seam where flooring 312 meets flooring 314. A seamless look by snapping connectors 60 together is difficult to get since the two flooring sides are laid independently. Flooring 312 and 314 are laid with about an inch of space between them, then the gap is covered with T molding 310. T molding 310 can optionally be glued down or snapped into a track in the gap between floorings 312 and 314. Because T molding 310 is formed from one of the same planks that are used to make one or both of floorings 312 and 314, the T molding matches the flooring almost perfectly.
The opposite side of middle 302 has a groove 180 formed to allow that side to fold down at 90 degrees, like the folds done with stair nosing 150.
Groove 110 can be used as well as groove 180. Groove 180 is non-symmetrical and can have shelf 188 disposed toward or away from middle 302.
The vertical lift of extension 322 allows top surface 104 to stay horizontal when flooring 325 is made from the same thickness of planks 100 as end molding 324. Extension 322 sits between two parallel surfaces, i.e., floor 326 and shelf 188, which helps strengthen end molding 324 from gap 330 being crushed by a person stepping on the end molding. Gap 330 can also be filled with an adhesive or something solid like a strip of plastic, wood, or metal to further strengthen end molding 324. An additional cut could be made into middle 302 to create a structure sized to be used with a metal track nailed down to the floor.
End molding 320, with shelf 188 oriented away from middle 302, could also be made with an extension 322 to lift the grooved side of the end molding. End moldings 320 and 324 are commonly used where LVP flooring ends and a totally different type of flooring is used, e.g., carpet. End moldings 320 and 324 match flooring 325 due to being made from the same planks 100 that the flooring is made from.
The above disclosed methods and devices are described with reference to luxury vinyl plank flooring but apply equally to other types of plank flooring that are sufficiently flexible. For instance, while the illustrated embodiment is made from a luxury vinyl plank (LVP), other type of flooring planks are used in other embodiments. Stone plastic composite (SPC), wood plastic composite (WPC), and engineered vinyl plank (EVP) flooring is a non-exhaustive list of other similar types of flooring that can be used in the above-described method to form molding out of flooring planks.
While two specific groove designs are disclosed, i.e., groove 110 and groove 180, other groove profiles can be used to allow a floor plank to be bent and used as a molding. Stair noses can be made using any number and angle of folds, e.g., three 60-degree angles could be used instead of two 90-degree angles to create a pointed nose. The total of all fold angles does not necessarily need to equal 180 degrees.
While one or more embodiments of the present invention have been illustrated in detail, the skilled artisan will appreciate that modifications and adaptations to those embodiments may be made without departing from the scope of the present invention as set forth in the following claims.
The present application is a continuation of U.S. patent application Ser. No. 17/336,925, now U.S. Pat. No. 11,873,645, filed Jun. 2, 2021, which claims the benefit of U.S. Provisional Application No. 63/034,204, filed Jun. 3, 2020, which applications are incorporated herein by reference.
Number | Date | Country | |
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63034204 | Jun 2020 | US |
Number | Date | Country | |
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Parent | 17336925 | Jun 2021 | US |
Child | 18399929 | US |