Improvements relating to floor mats
[0001] 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.
[0002] 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.
[0003] Various proposals have been made in the past to minimise or prevent creep of the
mat. One such proposal is our earlier GB Patent 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.
[0004] An alternative system is disclosed in our GB Patent 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 potion on the under-lying platen and the high
friction or "stiction" between mat and platen effectively prevents movement of the
mat.
[0005] 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.
[0006] 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.
[0007] We have found that a particularly simple system is provided by using, as detent in
a combination essentially according to the above-mentioned GB Patent 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.
[0008] 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 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] 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. The
invention also includes a set of carpet tiles for laying a carpet-tiled floor, the
set also including 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.
[0018] 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 × 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 × 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 × 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.
1. 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 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.
2. A system as claimed in claim 1, wherein the tiled floor is a floor provided with carpet
tiles of essentially the same surface area and shape and composed of a backing and
a fibrous or pile upper surface.
3. A system as claimed in claim 1 or 2, wherein the detent tile is of the same greater
thickness over its entire surface.
4. A system as claimed in claim 3 wherein the detent tile has a thickness from 0.3 to
0.6cm greater than the thickness of nearby tiles and the recess in the floor mat is
from 0.3 to 0.6 cm deep.
5. A system as claimed in any of claims 1 to 4, wherein the upper surface of the detent
tile is smooth and free from fibrous or pile material.
6. A system as claimed in any of claims 1 to 5, wherein a plurality of detent tiles of
significantly greater thickness are provided to underlie a floor mat having a recess
or a plurality of recesses in its back surface arranged to engage with the extra thickness
of the detent tiles.
7. A system as claimed in any of claims 1 to 6, wherein the floor mat has a backing of
rubber or plastics material in which the recess is formed and the backing is made
thicker around the perimeter of the recess and tapers towards the periphery of the
mat.
8. 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 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.
9. A set of carpet tiles for laying a carpet-tiled floor, the set also including 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.