System for Holding Carpet in Place Without Stretching

The invention relates to carpet installation and carpet cushion or padding, and more particularly to a system for adhering a pad to the floor and a carpet to the pad, eliminating any need for carpet stretching.

In the prior art, carpeting has been installed on floors in several different ways. In the conventional tackless strip system, the so-called tackless strip is secured to the floor around the walls of the room, the carpet is hooked onto the upwardly protruding nails of the tackless strip at one side of the room, and the carpet is stretched before it is hooked to the tackless strip at the opposite side of the room. The problems with this system are that it requires the installation of the tackless strip, which is time-consuming and which is difficult when concrete floors are encountered, and also that it requires a trained professional to re-stretch the carpet in the event a corner or edge portion of the carpet needs to be temporarily taken up for installation of wiring, access to the floor or for drying a carpet which has been wetted.

Many carpet installations involve gluing of the carpeting to the floor, without any carpet cushion or pad between the carpet and the floor. With this system, the carpeting can be of less expensive construction, with a primary backing but without the need for a secondary backing which is generally required for stretched carpeting. The glued-down carpeting avoids wrinkling without the need for stretching, but loses the benefit of a carpet pad. Also, the carpet can be very difficult to remove either for replacement or temporarily, for maintenance, without destroying the floor or the carpeting itself due to the adhesion of the glue.

In glue-down installations, the carpet is ordinarily laid on the floor first and seamed as required. The glue is then applied to the floor, either in liquid form or by spraying it onto the floor. This can be accomplished by folding back half of the carpet, applying the glue to the floor in that area, and dropping the carpet in place to adhere it to the floor in that area. The opposite side of the carpet could then be folded back, glue applied to the floor in that area, and that portion of the carpet then adhered to the floor.

Another installation system wherein the carpet was adhered to the floor without padding is disclosed in U.S. Pat. No. 4,405,668. This system used a separate, thin scrim web with adhesive on both sides and with a release film on one side. The scrim web was placed on a floor with the release film on the upper surface, adhering the web to the floor, whereupon the carpet could then be seamed and cut as required while lying on top of the release film. The carpet was then folded back and the release film removed in one area, that portion of the carpet was pressed down, and the operation was repeated in another area. This system was relatively expensive and still did not permit the installation of a carpet pad beneath the carpeting. A similar construction of adhesive webbing material is shown in U.S. Pat. No. 4,234,649.

In yet another system for installing carpet without stretching, a slab or pad of jute material was interposed between the carpet backing and the floor. In this particular system the floor was sprayed with a wet adhesive, the slab of jute material was laid into the adhesive while the adhesive was still wet, the top surface of the jute material was sprayed with the wet adhesive; and the carpet was laid on the wet adhesive on the top surface of the jute slab or pad. The wet adhesive, as it dried, became enough of a pressure sensitive adhesive to permit the carpet to be pulled up and removed.

This system had the disadvantage of being an expensive system because of the costs required to make an on-the-job installation.

It is a primary object of the present invention to hold carpet in place without stretching by a system that avoids the problems of the prior art.

It is a closely related object to hold the carpet in place by a system that utilizes a pad with pressure sensitive adhesive on the upper and lower surfaces of the pad.

By the method of the present invention, carpeting is efficiently and economically installed without stretching or the need for tackless strips and without liquid glues or spray adhesives, but still with the benefit of a carpet cushion or pad between the floor and the carpet.

First there is positioned on the floor surface a carpet cushion having a pressure-sensitive adhesive on both its upper and lower surfaces, with a release film adhered to the adhesive on the upper surface. The carpet cushion also includes a means for maintaining dimensional stability. The cushion is laid and trimmed as required.

Next the carpet is positioned on top of the release film on the carpet cushion, and rough cut and seamed as required. The carpet is then folded back to expose a portion of the carpet cushion, usually one half, and the release film is removed from the exposed cushion.

The carpet is then pressed down onto the exposed pressure-sensitive adhesive on the upper surface of the carpet cushion, and another portion of the carpet is folded back and the release film is removed from that area of the carpet cushion. That portion of the carpet is then pressed down.

When all areas of the carpet are in contact with the adhesive, final trimming of the carpet edges is performed.

The described method may include installing rigid spacer strips on the floor along the walls of the room before laying the carpet cushion, preferably strips of wood or plastic with pressure-sensitive adhesive on both sides. The purpose of the spacer strips is to provide an edge similar to that of the tackless strips, since the carpet installer's trimming tools have been designed to trim the carpet with the hard strip present, cutting the carpet 1/4 inch long and tucking the carpet edge under, against the wall or baseboard. If a tackless strip from a previous carpet installation is present, it may be left in place with no need for the spacer strips.

The means for maintaining dimensional stability in the carpet cushion preferably comprises a scrim webbing of a fibrous plastic material, such as polyester "leno weave" square webbing, bonded to each surface of the synthetic foam pad of the cushion material. In the manufacture of the carpet cushion, a sealant preferably is applied to both scrim-covered surfaces of the foam pad to substantially seal the surface, before the pressure-sensitive adhesive is added. This keeps the adhesive at the surface of the foam.

In another embodiment the means for maintaining dimensional stability simply comprises a stiffened surface or crust at both the lower and upper surfaces of the foam cushion. This can be accomplished by a heat process, for example, which may eliminate the need for any sprayed-on sealant on the surfaces of the foam.

The adhesive need not cover the entire surfaces of the carpet cushion, but may be in spaced strips on each surface. Adhesive cost is thereby reduced without adversely affecting the positional stability of the carpet installation. Also, this enables the carpet cushion to be stapled or tacked to the floor, if needed in particular areas, in the spaces between strips of adhesive on the upper surface. The carpet will then bridge the gap over the recess or dimple caused by the stapling, since there is no adhesive in this area.

The adhesive on the cushion's surfaces may be in parallel serpentine strips to discourage wrinkling of the carpet, which tends to occur in straight lines.

The system of the invention enables the use of less expensive carpeting than usually required in stretch/tackless strip installations. The typical stretched carpet includes the upper surface yarn, extending through a bonding mesh such as a polypropylene mesh, with a primary backing of latex and a secondary backing of a jute mesh for resiliency in the stretching operation.

With the present system of adhesive bonding of the carpet to the pad (and the pad to the floor), the carpet does not need an expensive secondary backing, since it is adhered down in substantially all areas and is not stretched.

It is therefore among the objects of the invention to improve on prior carpeting installation methods and systems by the use of a system including a carpet cushion or pad having pressure-sensitive adhesive at both surfaces, for adhering the cushion to the floor and the carpet to the upper surface of the cushion, avoiding the need for stretching or for relatively expensive carpeting which includes a secondary backing.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings, which by way of illustration, show preferred embodiments of the present invention and the principles thereof and what are now considered to be the best modes contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

FIG. 1 is a fragmentary sectional view showing a carpet and pad installed according to the system of the invention.

FIG. 2 is a perspective view showing a carpet pad according to the invention and comprising a part of the installation shown in FIG. 1. The pad is shown coming off a roll, with a release film covering one side of the adhesive-coated pad, on the inside of the roll.

FIG. 3 is a perspective view showing a floor in preparation for carpet installation according to the invention, with the pad laid on the floor and the carpet being unrolled on top of the pad over the release film.

FIG. 4 is a perspective view similar to FIG. 3, but showing the carpet pulled back for peeling away the release film from the top surface of the pad, in a portion of the floor where the carpet, already seamed and cut, has been pulled or rolled back.

FIG. 5 is a plan view showing a pad according to the invention with its pressure-sensitive adhesive applied in parallel strips rather than over the entire surface of the pad, and showing optional stapling between the strips of adhesive.

FIG. 6 is a plan view similar to FIG. 4, but showing the adhesive applied in serpentine strips.

FIG. 7 is a schematic view indicating a method for producing the carpet pad of the invention.

FIG. 8 is a view similar to FIG. 1, but showing another form of carpet and pad installation according to the invention.

In the drawings, FIG. 1 shows a carpet 10 with a pile 11 and a single backing layer or primary backing 12 laid on a pad or carpet cushion 13 comprising a foam pad 14 and a scrim webbing 16 bonded to both top and bottom surfaces of the pad 14, with a pressure-sensitive adhesive layer 17 also at top and bottom surfaces on the scrim 16 and on the surfaces of the pad 14 itself, between the mesh of the scrim webbing. The adhesive 17 holds the carpet backing 12 to the carpet cushion 13, and the carpet cushion to the surface of the floor 18 below.

FIG. 2 shows a roll 19 of the carpet cushion 13 of the invention, showing the foam pad 14 and the upper layer of scrim webbing 16 which is bonded to the pad 14 in the manufacturing process. The adhesive layer 17 has been applied after the scrim webbing 16, coating the outer surfaces of the webbing mesh 16 and the exposed areas of the pad surface 14 among the mesh. A release film 21 of a sheet plastic material overlies the upper surface of the carpet cushion 13, i.e., the inner surface of the cushion on the roll 19, being temporarily adhered to that surface. The bottom of the cushion 13, and thus the outer surface of the roll 19 as seen in FIG. 2, is not covered by any release film. This enables the cushion to be laid on a floor and adhered to the floor while still leaving the upper surface as a work surface for unrolling the carpet 10 and performing preliminary cutting and seaming operations as necessary. For storage and transport of the roll 19 prior to installation, the release film may have a tail or extension 20 (dashed lines) which wraps around the roll and covers the exposed adhesive.

The scrim webbing 16 gives dimensional stability to the adhesive carpet cushion 13, and helps enable the carpeting to be removed from the cushion, or the cushion to be removed from the floor 18, without destruction of the carpet or the cushion or the floor itself. The pressure-sensitive adhesive 17 is a non-permanent adhesive so as to always allow for temporary lifting of the carpet wholly or in localized areas when desired.

FIG. 3 illustrates some aspects of the installation operation according to the system of the invention. First, rigid spacer strips 22 may be installed around the edges of the room near the walls 23. The spacer strips 22 may be of wood or plastic, for example, with a pressure-sensitive adhesive 24 on both the upper and lower surfaces. The purpose of the strip 24 is merely to take the place of the conventional tackless strips, in the sense that conventional carpeting tools for trimming the finished carpet are designed to be used along the edges of the tackless strips. If tackless strips are in place from a prior carpet installation, they should be left intact, and the spacer strips 22 would then not be needed.

It should also be understood that the carpet installation according to the invention may be performed without the use of any spacer strips 22 or tackless strips provided the installer uses tools adequate to properly trim the carpet without the presence of the usual rigid strip.

The carpet cushion 13 is unrolled onto the floor along the spacer strips 22, which are of about the same thickness as the cushion, generally in the manner shown in FIG. 2.

As indicated in FIG. 3, the adhesive carpet cushion 13 is first laid and trimmed on the floor 18, with its lower side adhered to the floor 18 but the release film 21 remaining on the upper surface. The carpet 10 is then unrolled over the top of the release film, and seaming and preliminary cutting is performed as necessary.

With the carpet seamed and rough cut it is then folded back or rolled back as indicated in FIG. 4 to expose a portion 13a of the cushion. Carpet seaming is indicated at 25. This enables the release film 21 to be peeled off the upper surface of that portion of the cushion 13a as indicated in FIG. 4. Once this is accomplished, the carpet is put back into position on the sticky upper surface of the cushion portion 13a and the same operation is repeated with another portion of the carpet 10 which may be the other half of the room. That is, the carpet is pulled or folded or rolled back to expose another portion or the remainder of the carpet cushion and its release film 21 is peeled off. Then the remaining portion of the carpeting is moved back into position, until all areas of the carpet are in contact with the upper surface of the carpet cushion, and final trimming operations are conducted.

FIG. 5 shows a carpet cushion 13b according to the invention, with spaced strips of adhesive 17a upon the surface, separated by spaces 26 of the surface which have no adhesive. This saves on the amount of adhesive required while still providing for adequate adhesion of the carpet cushion 13b to both the floor and the carpet backing. Also, it enables staples 27 or tacks to be used to hold the carpet cushion 13b down to the floor if required under special circumstances, without causing the carpet to recess or "dimple" inwardly at the location of the staple. Dimpling is avoided because there is no adhesive in the immediate vicinity of each staple 27, so the carpet does not adhere into the recess in the cushion caused by the staple, but rather the carpet bridges across the recess.

FIG. 6 shows a serpentine pattern for adhesive strips 17b on a carpet cushion 13b, which may be desired to prevent a pattern of wrinkling in the installed carpet. Wrinkles tend to occur in straight lines, so that the serpentine pattern shown in FIG. 6 discourages the occurence of wrinkles.

As indicated in FIG. 7, in the manufacture of the adhesive carpet cushion 13, the scrim webbing 16 is bonded to both sides of the foam sheet 14, preferably as the foam pad 13 is being formed. The webbing 16b may be bonded to the surfaces of the pad 14 by a heat bonding process, as by heaters indicated at 30, so that it is fused into the surfaces of the foam pad during the manufacturing process, or it may be bonded by other suitable means such as adhesives. In any event, a sealant 31 preferably is applied, as by liquid application or spraying by spray nozzles 32 on both surfaces of the pad with the webbing attached. This substantially closes the porosity of the foam at the surfaces. Next, an adhesive 17 such as hot melt adhesive is applied to the webbing and foam surfaces, as by sprayers 33, and the adhesive does not penetrate into the foam due to the prior application of the sealant.

The release film 21 is next applied to one side of the carpet cushion 13, temporarily bonding to the adhesive on that side. Preferably, all of these operations are accomplished in a continuous process wherein the foam 14, scrim webbing 16 and release film 21 are advanced off roll stock 16a and 21a as schematically indicated in FIG. 7. The sealant and adhesive are applied at appropriate points in the operation, and the final product emerges complete and is stored in rolls 19 similar to that shown in FIG. 2.

In FIG. 8 a carpet 10 and pad installation is shown, using a modified form of adhesive cushion 40 according to another embodiment of the invention. The cushion 40 has no scrim webbing on either surface, but instead relies on a stiffness or "crust" 41 on each surface, with the adhesive 42 applied to these higher-density surfaces 41.

The cushion 40 preferably comprises a high-density urethane foam 43, which when heat-cured forms a skin or crust 41 of increased density. The skin 41 is dense enough that it seals the surfaces and closes the porosity, obviating the need for any sealant 31 (FIG. 7). With this skin, the adhesive 42 will not wick into the foam 43. Also, the skin is stiff enough to provide the required dimensional stability.

The foam cushion 40 may be either flat-surfaced or waffle-surfaced. A waffled surface may be preferable in that it uses less adhesive if the adhesive is rolled (rather than sprayed) onto the surface.

It should be understood that an adhesive carpet cushion according to the invention can be formed with scrim webbing on one or both surfaces, or none. Dimensional stability can be achieved with scrim on one surface only. If one surface has the scrim, it normally is the lower surface in the installation, since at that surface it is more important that the pad be removable from the floor without damage to the pad or the floor.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.