IMPROVEMENTS RELATING TO FLOOR MATS

Abstract: A non-creep floor mat system for a tiled floor (10) comprises a floor mat (12) having in its back surface a recess bounded by a substantially rigid essentially perpendicular wall, and a detent designed to underlie the floor mat on a floor surface and having a shape and size similar to but slightly less extensive than the shape and side of the recess in the back surface of the mat. The detent is a tile (11A) designed to form part of the tiled floor but having a thickness significantly greater than the thickness of nearby tiles (11) on the tiled floor,, whereby the extra thickness of the tile detent enables it to fit into and interact with the recess in the floor mat back surface to restrict or prevent creep of the floor mat over the tiled floor.

Description: The present invention relates to floor mats, more particularly to dust control mats which are placed on existing floor coverings in shops, offices and other premises to absorb dust, dirt and moisture from the shoes of people walking over them and which are then regularly removed for cleaning and maintenance and replaced or substituted by other mats of the same type. Such mats are conventionally composed of a rubber or plastics backing with a pile fabric extending over at least the central part of the upper surface. When a dust control mat or other floor mat is placed on an existing floor covering which has a fibrous upper surface, for example a continuous carpet or carpet tiles, there is a tendency for the floor mat to creep relative to the underlying floor covering. Various proposals have been made in the past to minimise or prevent creep of the mat. One such proposal is our earlier GB-A-2,115,693. That patent discloses a floor mat combination comprising one or more detents detachably securable to a floor surface and a mat having a back surface of flexible but substantially incompressible sheet material formed with one or more recesses whose side walls constitute substantially rigid abutments located within the perimeter of the mat and extending generally perpendicular to the mat, the abutment(s) on the mat being arranged so that when the mat overlies the detent(s) the abutment(s) on the mat abut against or are in close proximity to complementary abutment(s) on the detent and thereby restrict or prevent lateral movement and/or rotation of the mat relative to the detent. The detent can be a platen of wood, metal, plastics, rubber or other relatively rigid material fixed to the floor covering by adhesives, tape, screws, nails, pins or in any other convenient way or fixed to the underlying floor either directly or through the floor covering. In a simple embodiment the mat is rectangular and formed with a rectangular recess in its back surface and the detent is a rectangular platen or pad slightly smaller in area than the recess but of similar shape. An alternative system is disclosed in our GB-A-2,195,531 in which, instead of a recess in the mat, the mat is formed with an ultrasmooth portion on its back surface which interacts with an ultrasmooth portion on the underlying platen and the high friction or "stiction" between mat and platen effectively prevents movement of the mat. The combinations disclosed in the earlier patents give very satisfactory results. However, it can be a drawback to use a platen which has to be separately attached to the floor surface because that platen may be inconvenient or difficult to remove and may therefore be regarded as a fixture. This drawback is particularly significant where the underlying floor covering is composed of carpet tiles because an important advantage of carpet tiles is that they can be readily removed or changed, for example when they become dirty or worn. Creep is a particularly severe problem with mats placed on carpet tiles and it is important to provide a system which reduces or eliminates creep in such instances. It is therefore an object of the present invention to provide an improved non-creep floor mat system which is especially suitable for use in conjunction with a carpet-tiled floor. We have found that a particularly simple system is provided by using, as detent in a combination essentially according to the above-mentioned GB-A-2,115,693, one or more tiles of a greater thickness than usual. Such tiles can be included in the normal array of carpet tiles on the floor but their greater thickness causes them to extend above the surface of the surrounding tiles and form detents engaging with complementary recesses in overlying dust control mats. According to the invention there is provided a non-creep floor mat system for a tiled floor comprising a floor mat having in its back surface a recess bounded by a substantially rigid essentially perpendicular wall, and a detent designed to underlie the floor mat on a floor surface and having a shape and size similar to but slightly less extensive than the shape and size of the recess in the back surface of the mat, characterised in that the detent is a tile designed to form part of the tiled floor but having a thickness significantly greater than the thickness of nearby tiles on the tiled floor, whereby the extra thickness of the tile detent (hereinafter referred to as the anchoring tile) enables it to fit into and interact with the recess in the floor mat back surface to restrict or prevent creep of the floor mat over the tiled floor. The tiled floor will normally be a carpet-tiled floor, that is to say a floor covered with carpet tiles composed of a backing and a fibrous or pile upper surface. The tiles may be loosely laid on the underlying floor surface or may be attached to it, e.g. with adhesive, in any convenient or conventional manner. The tiles may be of any shape which will tile a floor and need not all have the same size or shape although for convenience they are all of the same surface area and shape and are suitably square. The extra thickness of the anchoring tile acting as detent as compared with neighbouring carpet tiles must be sufficient to permit significant interaction between the exposed parts of the edges of the tile and the wall of the recess in the floor mat and is preferably at least 0.3 cm. However, it should not be significantly more than the thickness of the floor mat, otherwise it will cause unevenness in the floor mat upper surface and may trip an unwary walker. For use with conventional dust control mats its thickness will usually be not more than 0.6 cm. The upper surface of the anchoring tile is preferably free from the fibrous or pile material which covers the upper surface of the ordinary carpet tiles in order to make it more readily identifiable and it may be made smooth., even ultra smooth to take advantage of the principle of "stiction" mentioned in our GB Patent 2,195,531. In such a situation the extra thickness of the anchoring tile and the depth of the recess may be reduced or possibly even eliminated because of the good friction between the tile and the back surface of the mat. The anchoring tile may be made of similar essentially incompressible material to the backing used on ordinary carpet tiles, for example bitumen or polyvinyl chloride. If desired, the anchoring tile could be manufactured so that not all of it is of greater thickness, the region of greater thickness forming a projection from the upper surface of the remainder of the tile, but such a construction would be more difficult to produce and would not lead to further advantages. If desired, the tiled floor may be provided with more than one anchoring tile of extra thickness. These may be relatively close to or even touching one another so that they are overlain by the same floor mat, which is then provided with a plurality of recesses to accommodate their extra thickness, or they may be more widely separated so that they interact with different floor mats. When the tiles are not permanently fixed to the underlying floor the anchoring tiles may be moved from point to point around the floor as required or desired. The floor mat may be a dust control mat or other mat and its backing may be made of rubber or plastics material or other convenient, usually washable material. The backing of the mat may be flexible but is intended to be substantially incompressible so that the side wall of the recess or recesses formed in it is substantially rigid. This ensures that, when the side wall of the mat recess moves into abutting contact with an exposed edge of the anchoring tile, essentially no further deformation of either occurs, such as would lead to further movement of the mat in the same direction relative to the underlying tile. Synthetic rubbers and plastics such as nitrile rubber are conveniently used for the backing of the mat. The depth of the recess in the mat should be correlated with the extra thickness of the underlying anchoring tile so that there is sufficient contact to prevent movement. Too little contact can lead to overriding. Preferably the depth of the recess is 0.3 to 0.6 cm. If the mat has a normal backing thickness greater than the desired recess depth the recess can simply be an area thinner than the remainder of the backing. Usually, however, the backing is made thicker around the perimeter of the recess and tapers towards the periphery of the mat, being often as thin at the periphery of the mat as in the recess itself or even thinner. The shape of the recess should be similar to the shape of the underlying anchoring tile, i.e. it should preferably be square when the tiles are square, but its area should be slightly greater to enable the anchoring tile to fit into it. The extra area can be very small, 3 % or less, when it is desired to prevent essentially any movement, or can be somewhat larger, up to 15 % or more, when some movement is permissible. It might be conceivable to produce a system in which the mat was provided with an area of increased thickness rather than a recess and the tile detent was correspondingly thinner than surrounding tiles or was absent entirely but it is not seen that such a system would have advantages. It will be apparent from the above that the invention also includes a process for providing a carpet-tiled floor which comprises laying carpet tiles on a floor surface and is characterised in that one or more anchoring tiles which have a greater thickness than surrounding carpet tiles are included in the layout and in that a floor mat having a recess in its back surface of a shape and size similar to but slightly larger than the shape and size of the anchoring tile(s) is laid on top of the carpet-tiled floor so that its recess fits over the anchoring tile (or one of the anchoring tiles), whereby creep of the mat relative to the carpet-tiled floor is restricted or prevented. A set of carpet tiles for use in the above process includes at least one anchoring tile of significantly greater thickness than the other tiles and preferably free from fabric or pile material on its upper surface. One embodiment of the invention is illustrated by the accompanying drawing in which a floor surface 10 is provided with a floor covering of square carpet tiles 11 of size 50 x 50 cm, one of which 11A is about 0.3 cm thicker than the others (1.2 cm as compared with 0.9 cm) and lacks the fibrous or pile material on its upper surface which is present on the other tiles. A dust control mat 12 of size 80 x 120 cm and overall thickness about 1 cm having a pile fabric on its upper surface apart from a narrow border and a backing 13 of nitrile rubber is provided with a square recess 14 of size 51 x 51 cm and depth 0.3 cm. Around the perimeter of the recess the backing has a thickness of 0.47 cm and it tapers to a thickness of 0.17 cm at the periphery of the mat. This is placed over the anchoring tile 11A and surrounding tiles so that its recess 14 fits over the tile 11A. Movement of the mat more than 1 cm in any direction as a result of creep is prevented by the essentially incompressible side walls of the recess 14 abutting against the essentially incompressible exposed edges of the mat 11A.

Claims: A non-creep floor mat system for a tiled floor comprising a floor mat (12) having in its back surface a recess (14) bounded by a substantially rigid essentially perpendicular wall, and a detent designed to underlie the floor mat on a floor surface and having a shape and size similar to but slightly less extensive than the shape and size of the recess in the back surface of the mat, characterised in that the detent is an anchoring tile (11A) designed to form part of the tiled floor but having a thickness significantly greater than the thickness of nearby tiles (11) on the tiled floor, whereby the extra thickness of the anchoring tile (11A) enables it to fit into and interact with the recess (14) in the floor mat back surface to restrict or prevent creep of the floor mat (12) over the tiled floor. A system as claimed in claim 1, wherein the tiled floor is a floor provided with carpet tiles (11) of essentially the same surface area and shape and composed of a backing and a fibrous or pile upper surface. A system as claimed in claim 1 or 2, wherein the anchoring tile (11A) is of the same greater thickness over its entire surface. A system as claimed in claim 3 wherein the anchoring tile (11A) has a thickness from 0.3 to 0.6cm greater than the thickness of nearby tiles (11) and the recess (14) in the floor mat (12) is from 0.3 to 0.6 cm deep. A system as claimed in any of claims 1 to 4, wherein the upper surface of the anchoring tile (11A) is smooth and free from fibrous or pile material. A system as claimed in any of claims 1 to 5, wherein a plurality of anchoring tiles (11A) of significantly greater thickness are provided to underlie a floor mat (12) having a recess or a plurality of recesses (14) in its back surface arranged to engage with the extra thickness of the anchoring tiles (11A). A system as claimed in any of claims 1 to 6, wherein the floor mat (12) has a backing (13) of rubber or plastics material in which the recess (14) is formed and the backing (13) is made thicker around the perimeter of the recess (14) and tapers towards the periphery of the mat (12). A process for providing a carpet-tiled floor which comprises laying carpet tiles on a floor surface, characterised in that one or more anchoring tiles (11A) which have a greater thickness than surrounding carpet tiles (11) are included in the layout and in that a floor mat (12) having a recess (14) in its back surface of a shape and size similar to but slightly larger than the shape and size of the anchoring tile(s) (11A) is laid on top of the carpet-tiled floor so that its recess fits over the anchoring tile (11A) (or one of the anchoring tiles), whereby creep of the mat (12) relative to the carpet-tiled floor is restricted or prevented.

Inventors: BRAZIER, PETER CHARLES
Applicants: WALK OFF MATS LIMITED
Application year: 1990
Main classification: A47G27
IPC codes: A47G27