Note: Descriptions are shown in the official language in which they were submitted.
CA 02809741 2013-03-15
1
Title: SURFACE FOR CONTROLLING LIQUIDS
FIELD OF THE INVENTION
The present invention relates to the field of liquid spill control. More
particularly, the invention pertains to surfaces for liquid spill control.
BACKGROUND OF THE INVENTION
There are a number of different applications in which surface mats may
be used for the control of liquids. These applications include car surface
mats
for controlling slush, snow, and water falling from the shoes and boots of
drivers
and passengers. Such liquid controlling surfaces may also be used as platforms
for storing wet shoes and boots at house and office entrances. Such surfaces
may also be used to control water falling from a person who has just exited a
bath or shower.
There have been previous attempts to manage liquid spills using mats.
For example, U.S. patent 5,776,583 ("Peyton") discloses a surface mat system.
In the Peyton surface mat, a plurality of rectangular cells are formed, with
each
cell having a drain hole 14. The drain holes 14 are formed in a continuous
web,
which web overlies a hollow portion supported by a plurality of pillars 36.
Liquid
contacting the mat goes through the drain holes into the hollow portion.
There are a number of problems with the Peyton design. First, the
Peyton design requires a complex two-layer structure, complete with cells, a
lower hollow portion, and pillars to maintain the structural integrity of the
mat.
Without the complex series of pillars, the mat would be crushed or broken by a
heavy weight placed upon it, and the water would squirt out through the drain
holes. Second, the area of the mat between the cells, where a person's pant
leg or shoe might rest, contains a substantial amount of flat surface area on
which liquid can collect, thus undesirably coming into contact with clothing.
U.S. patent No. 4,246,982 ("Pretnick") discloses a mat having a plurality
CA 02809741 2013-03-15
2
of ribs that define rectangular chambers. A center tray section is positioned
between the two sets of rectangular chambers. As shown in Figure 7, the inner
sides of the sets of chambers 12 and 14 are provided with drain holes 61 to
provide drainage of drippings into the center of the tray and then out through
a
garden hose drain attachment at 32.
This configuration is complex to manufacture, in that it requires
manufacture of separate tray and rib sections. Furthermore, this configuration
also presents a substantial surface area that can easily come in contact with,
and undesirably transfer liquid to, objects such as shoes or clothing.
SUMMARY OF THE INVENTION
Therefore, what is desired is a liquid controlling surface that is effective
in controlling spills and that can be simply constructed. Preferably, the
surface
will be configured to distribute liquid from the point of origin of a spill to
other
portions of the surface while still controlling the liquid. Preferably, the
liquid
controlling surface is configured to reduce the likelihood of liquid being
transferred from the surface to an object resting thereon.
Therefore, there is provided a liquid controlling surface comprising:
a formation comprising a plurality of individual open topped, closed
bottomed cells for containing liquid, each of said cells having a cell wall
defining
a well;
a plurality of distribution channels extending between adjacent cells and
being positioned on the cell wall at a height to permit liquid to drain to the
adjacent cell when a cell liquid level exceeds a predetermined limit and to
permit
liquid to be retained in said well up to said limit; and
a perimeter wall surrounding said cells and being free of distribution
channels from said cells, the perimeter wall having a height higher than said
distribution channels to prevent liquid from leaking from said cells to an
area
outside the perimeter wall.
CA 02809741 2013-03-15
3
Optionally, each distribution channel is configured so as to prevent an
object resting on top of the internal cell wall from contacting liquid in the
cells or
the distribution channel. Preferably, to create a surface that minimizes the
transference of liquid when contacted, the internal cell walls are tapered
towards
their tops so as to reduce the potential contact area between the surface and
an object resting thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made, by way of example only, to the drawings,
which illustrate the referred embodiment of the invention, and in which:
Figure 1 is a perspective view of one embodiment of the surface;
Figure 2 is a perspective view of a second embodiment of the surface;
Figure 3 is a perspective view of a third embodiment of the surface;
Figure 4 is a perspective view of a fourth embodiment of the surface;
Figure 5 is a perspective view of a fifth embodiment of the surface;
Figure 6 is a plan view of a single cell of the surface shown in Figure 1;
Figure 7 is across-sectional elevation view taken along line 7-7 of Figure
1;
Figure 8 is a plan view of a single cell of the surface shown in Figure 2;
Figure 9 is a cross-sectional elevation view taken along line 9-9 of Figure
2;
Figure 10 is a plan view of a single cell of the surface shown in Figure 4;
Figure 11 is a cross-sectional elevation view along line 1 1-1 1 of Figure
4;
Figure 12 is a cross-sectional elevation view, similar to that of Figure 11,
of a cell having a generally circular convex contact surface;
Figure 13 is a plan view of a single cell of the surface of Figure 5;
5; Figure 14 is a cross-sectional elevation view along line 14-14 of Figure
CA 02809741 2013-03-15
4
Figure 15 is a perspective view of an embodiment of the surface that
includes a reservoir; and
Figure 16 is an exploded view of the surface of Figure 15.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to Figures 2, 8, and 9, a liquid controlling surface 10
according to a first embodiment of the present invention is shown. The surface
comprises a perimeter wall 12 for preventing liquid contained in the surface
10 from leaking to an area outside the wall 12. The perimeter wall 12
surrounds
10 a formation 14 comprising a plurality of individual cells 16 for
containing liquid.
Each cell 16 comprises a cell wall 18, which may comprise one or more wall
sections 20. In the preferred embodiment, each cell includes a well 22 to hold
the liquid, and the well 22 is defined by, and preferably surrounded by, the
wall
18.
Preferably, the cells 16 are generally rectangular in plan view (i.e. when
viewed from above the surface) and open topped. It will be appreciated that
such an open topped cell shape is preferred, because it facilitates the
manufacture of surfaces 10 in, for example, a convenient rectangular shape.
However, the invention comprehends other shapes for the cells 16, as described
in more detail below. What is required is for each cell to comprise a well to
contain a volume of liquid within the cell.
The mat further includes a plurality of distribution channels 24 between
the wells of adjacent cells. In the most preferred embodiment there is a
distribution channel 24 connecting each cell 16 to each adjacent cell 16, but
less
could be used without departing from the scope of the present invention. Each
distribution channel 24 is positioned on the internal cell wall 18 at a height
so as
to channel liquid to the adjacent cell 16 when a cell liquid level exceeds a
predetermined limit. It will be appreciated that, preferably, this limit is
determined by the height of the channel 24 on the wall 18, relative to the
bottom
of the well of the cell. When the liquid level within a well 22 reaches the
height
CA 02809741 2013-03-15
,
5
of the channels 24, any additional liquid will be channelled to an adjacent
cell
16 through gravity. The higher the channel 24 on the wall 18, the higher the
limit, and the more liquid can be held within the well 22 before additional
liquid
is channelled or permitted to drain to an adjacent cell 16.
Preferably, the perimeter wall 12 will have a height higher than that of the
channels 24 to prevent liquid from leaking from the cells 16 to an area
outside
the perimeter wall 12. Also, preferably, this will prevent liquid from moving
onto
the top of the perimeter wall 12 itself, thus lessening the probability that
an
object (e.g. a shoe of a user), will have liquid transferred onto it from the
top of
the perimeter wall 12.
In the preferred embodiment, the channels 24 are arcuate depressions
in the walls 18, open to the top of the surface 10. However, it will be
appreciated that the channels 24 can take other forms. For example, the
channels could take the form of the holes in the walls 18, wherein the hole is
surrounded entirely by the wall 18, and is not open to the top of the surface
10.
As another example, the channels 24 can be squared, or V-shaped. Other
shapes are also comprehended by the invention. The use of channels 24 that
are arcuate depressions in the walls 18 is preferred because such channels 24
are relatively simple to create in a rubber moulding process that can be used
to
manufacture the surface 10.
Preferably, the channels 24 are configured so as to prevent an object
resting on the walls 18 from contacting liquid in the cells 16 or channels 24.
It
will be appreciated that one preferred feature of the surface is to control
spilled
liquid while preventing the liquid, to the extent possible, from being tracked
around, and from wetting the shoes and/or clothing of someone contacting the
surface. The preferred surface reduces the likelihood of this outcome by
preventing an object from contacting the liquid in the well 22 or channels 24.
In the preferred form of the invention the channels limit the level of liquid
which can be retained in the wells 22 to a level below the tops of the cell
walls.
The exact height of the channels 24 will vary, depending upon the application
CA 02809741 2013-03-15
,
6
in which the surface of the present invention is being used. For example, fora
surface comprised of a flexible material which has to carry a heavy load, the
liquid level may be set quite low, at or about one third of the height of the
cell
wall. In other applications, where the cell wall is more rigid or the load is
lighter,
the liquid level of the cell can be higher, up to about 80% of the cell wall
height.
Even higher liquid levels can be used, but the risks of not being able to
prevent
contact between the liquid and an object resting upon the liquid are higher so
these higher levels are generally less preferred. In summary, a preferred
range
for the height of the channels is between 20% to 80% of the total cell wall
height, with between 40% and 60% being the most preferred range of heights.
It will be also understood that another factor influencing the preferred
height of the drainage channels is the type of liquids spills that the surface
is
intended to encounter. If the drainage channels are lower, then spills can
more
quickly disperse through the correspondingly larger sized drainage channels.
Conversely higher walls, while permitting each well to retain a larger volume
of
fluid will take longer to disperse the fluid across the adjoining cells.
It will be appreciated that the surface 10 can take various forms and still
be comprehended by the invention. The surface 10 may take a conventional
form, namely, a one-piece surface-covering element. However, for example, the
surface 10 may have a multi-piece, modular construction. In this
configuration,
surface elements can be manufactured, and multiple elements connected
together to build surfaces whose size and shape can be varied according to the
circumstances in which the surface 10 will be employed. As another example,
the surface 10 can be used in association with modular flooring and the like.
In
modular flooring, the floor in a location is built in modules and the modules
are
laid down adjacent to one another to form the floor. The invention comprehends
the surface 10 taking the form of a floor module. In this application, the
floor
module consisting of the surface 10 can be built right into the floor, and
positioned to perform its desired function.
CA 02809741 2013-03-15
7
Preferably, the surface 10, including the formation 14 and wall 12, is
composed of a somewhat flexible water-resistant material, such as moulded
rubber, most preferably rubber sourced from recycled tires. This embodiment
is preferred for a number of reasons. First, a moulding process is efficient
for
manufacturing large numbers of surfaces 10 relatively inexpensively. Second,
the use of recycled tire rubber puts such material to good use, thus reducing
the
need to dispose of used tires. Third, a moulding process is effective in
producing a surface 10 wherein the formation 14 and wall 12 have a unitary
(i.e.
one-piece) construction. With such a construction, a mat or surface
application
10 can be produced in one moulding step, and the basic components of the
surface 10 (the formation 14 and wall 12) are easily usable and manipulable -
there is no need to deal with multiple pieces.
It will be appreciated, however, the surface 10 may be manufactured in
any suitable way and still be comprehended by the invention. For example, the
surface 10 may be made of plastic. The surface 10, whether made of plastic or
another material, may be made from material recycled from a pre-existing use
or product. In addition, the surface 10 may be moulded, or manufactured using
a different process.
According to another aspect of the present invention, the surface 10 is
configured so as to reduce the contact area between the surface 10 and any
object resting thereon. It will be appreciated that, for many of the possible
uses
of the surface 10, it is desirable for the liquid to remain in the surface 10,
and
not touch an object that comes in contact with the surface 10. For example, if
the surface 10 is used to catch water and slush brought into vehicles by
riders
in the vehicles, it is desirable that the skirts and pants of riders not get
wet if
they come in contact with the surface 10. As another example, the surface 10
may be used to catch liquid spills from cars or trucks being repaired. It will
be
appreciated that oil, coolant fluid, brake fluids and the like from cars often
undesirably stain surfaces, driveways, and other similar surfaces. The surface
10 can be positioned under the car or truck during repair to control oil
spills. In
CA 02809741 2013-03-15
8
this application, it is also desirable that oil not be transferred from the
surface
to shoes, clothing, or car tires.
For the most part, the liquid contacting the surface 10 will enter the wells
22 of the cells 16. However, some of the liquid will remain, in a thin layer,
on the
5 contact area presented by the upper side of the surface 10. Thus, to reduce
the
likelihood of transferring such liquid to an object coming in contact with the
surface 10, the walls 18 are preferably tapered towards their tops 26 so as to
reduce the contact area between the surface 10 and an object resting thereon.
Most preferably, the walls 18 are tapered at their tops 26 substantially to a
point
10 (i.e. a pointed edge as shown in Figure 2). Thus, these points will
constitute the
reduced contact area between the surface 10 and an object resting thereon, in
contrast to untapered walls.
In addition, such a tapered top edge of the cell wall permits any liquid
which comes into contact with the water-resistant upper edge of the cell wall
to
quickly drain off the upper edge and into the wells below on either side of
the
wall. In this way, even if the upper edge is wetted with such a liquid in the
beginning, the sloped drainage surface will carry the liquid down away from
the
upper edge of the cell wall.
It will be appreciated that the tapered construction further provides good
structural integrity to the walls 18, because the walls 18 are thicker at
their
bases than at their tops. Thus, it has been found that a surface 10 with this
configuration can carry substantial weight without the walls 18 being crushed
or
broken. Thus, for example, in the car repair application, the tapered
construction allows a car to drive on the surface 10 without crushing or
deforming it, while the pointed tops 26 present a reduced contact area that
prevents the car from tracking substantial amounts of oil onto the ground with
its wheels. Of course, it will be appreciated by those skilled in the art that
the
strength of the flexible material used in forming the surface 10 will have a
bearing on the load capacity of the cell wall 18. Further, the size of the
individual cells 16 will determine how much of any given area of the surface
10
CA 02809741 2013-03-15
9
is comprised of open wells 22 as compared to load supporting walls 18. Thus
the size of the walls 18, the size of the cells 16 and the typical load being
supported can be used, in conjunction with the strength of the material from
which the surface 10 is made, to determine the optimal dimensions for both the
cell wall thickness and cell size.
It will be appreciated, however, that for some uses of the surface 10,
reduction in contact area is less important, while other factors are more
important. For example, in one preferred application of the present invention,
the surface 10 is used in a bathroom for gathering dripping liquid as a person
steps out of a shower or bath. In such a case, the user's bare feet will
contact
the surface 10. While preventing water from contacting the user's feet is not
particularly important in this case, because the user is already wet, it is
preferred
that the surface 10 be comfortable against the user's feet, and that the
surface
have a sufficient liquid retaining capacity to hold the liquid dripping off
the
bather.
Figures 1, 6, and 7 show a liquid controlling surface 10 having walls 18
whose tops 26 are rounded, thus providing somewhat more comfort to the feet
of the user. In this configuration, the walls 18 are tapered towards their
tops 26
so as to reduce the contact between the surface 10 and an object resting
thereon. However, the walls 18 form non-pointed contact areas. It will be
appreciated that rounded tops 26 are less likely than pointed tops to dig
uncomfortably into a user's foot. Further, since in this application of the
invention it is desirable to retain the dripping water, the distribution
channels can
be set to a higher level to permit more liquid to accumulate in each well. In
this
case the use of the channel at 80% of the total wall height might be
preferred.
In the embodiment of the surface 10 shown in Figure 3, the walls 18 are
tapered toward their tops 26 so as to reduce the contact area between the
surface 10 and an object resting thereon, but the tops 26 are not pointed.
Rather, in the embodiment of Figure 3, the tops 26 are non-pointed, narrow,
horizontal surfaces which form the contact area between the surface 10 and an
CA 02809741 2013-03-15
10
object resting thereon. It will be appreciated that this configuration of the
tops
26 would also be more comfortable to the foot of the user than the pointed
configuration.
Figures 4, 10, and 11 show a further embodiment of the surface 10. In
the embodiment of Figures 4, 10, and 11, the cells 16 and walls 18 are sized
and shaped so as to provide contact areas that are generally circular in plan
view. In other words, when viewed from above the surface 10, the contact
areas are generally circular. It will be appreciated that such a
configuration,
which provides a substantial flat contact area, is quite comfortable for the
foot
of the user relative to a configuration where the tops 26 are pointed and
provides a relatively large well volume between the contact areas.
Yet another embodiment of the surface 10 is shown in Figures 5, 13, and
14. In this embodiment, the walls 18 and cells 16 are sized and shaped so as
to provide contact areas that are generally octagonal in plan view. Like the
circular contact areas of Figure 4, these octagonal contact areas provide a
substantial flat contact area, which provides comfort to the foot of a user.
Figure 12 shows a variant of the embodiment shown in Figure 4.
Specifically, in the variant shown in Figure 12, the contact areas are
generally
circular in plan view, and are also convex, i.e. they are not flat, but they
bulge
outward toward an object resting on the surface 10. It will be appreciated
that
this configuration is particularly useful for shower and bath surfaces,
because
the convex contact areas can produce a pleasant, massage-like feeling on the
soles of a user's feet. As well, because the contact area bulges outward from
the surface 10, liquid on the contact surfaces is encouraged to drain towards
adjacent cells.
It can now be appreciated how the surface 10 functions. The surface 10
includes a plurality of cells 16, each of which has a well 22 for holding
liquid.
Each well 22 has a predetermined cell liquid level limit, which, in the
preferred
embodiment, is the level above which liquid will be channelled to adjacent
cells
16. When a cell 16 reaches its limit, additional liquid is channelled 10
adjacent
CA 02809741 2013-03-15
11
cells 16. When adjacent cells 16 reach their limit, liquid is channelled to
other
adjacent cells 16. Thus, when a spill takes place on one portion of a surface
10,
once the capacity of the cells 16 that initially receive the spill is
exceeded, liquid
is automatically channelled to adjacent cells 16 by gravity, which will
continue
to distribute the liquid to additional cells 16 if their well capacity is
exceeded.
Thus, as liquid is distributed progressively further from the point of origin
of the
spill, more and more cells 16 are brought into service to contain liquid from
that
spill. The number grows exponentially as liquid from the spill moves outward
from the spill's point of origin. The higher the number of cells 16 in use to
contain the spill, the less the amount of liquid that each channel needs to
distribute to adjacent cells. In other words, during and immediately after a
spill
at a particular point on the surface 10, the one or more cells 16 at the point
of
origin of the spill will channel a relatively high volume of liquid to
adjacent cells.
However, each cell on the surface 10 has adjacent cells, and each of these
adjacent cells itself has adjacent cells, and so on. Thus, after the spill is
complete, the liquid is distributed over a much wider area of the surface 10
than
the immediate spill area, with a large number of cells 16 holding and
distributing
the liquid from the spill.
Thus, for example, it will be appreciated that if the surface 10 is on a level
surface, and all of the cells within the formation are filled up to the height
of their
respective distribution channels, any additional liquid from a new or
continued
spill received in the formation would be disseminated equally between all
cells
within the formation, regardless of the distance from the location of the new
or
continued spill.In addition, the shaping of the cells 16, walls 18, and tops
26 can be
varied to achieve particular results. In many uses, it is preferred to
minimize the
contact area between the surface 10 and an object resting thereon. The reason
for this is that liquid left on the contact area might be undesirably
transferred to
the object resting on the surface 10. Thus, by giving the walls 18 a shape to
minimize contact area, and to quickly drain such undesirable transfer of
liquid
CA 02809741 2013-03-15
12
can be minimized. This goal of reducing contact area may be achieved by walls
18 having the pointed tops 26. It is also achieved, to a lesser extent, by the
shaping of the walls 18 and cells 26 as shown in Figures 1 and 3, for example.
For other uses, the transfer of liquids from the surface to an object is less
of a
concern, but the comfort of a user is a greater concern. An example of such a
use is when the surface 10 is being employed as a surface in a bathroom
outside of a bath or shower. In such a case, the user's bare feet will be on
the
surface. As explained above, the shaping of walls 18 and tops 26 shown in
Figures 1, 4, 5, and 12 will provide greater comfort to a user's bare foot. In
particular, the contact area shown in Figure 12, namely, a plurality of convex
circular contact areas, provides a comfortable and pleasant feeling to a
user's
foot.
In addition, it will be appreciated that the cells 16 and distribution
channels 24 are sized, shaped, and mutually positioned to reduce the
likelihood
that an object resting on the surface 10 will come into contact with liquid
contained within the surface 10.
This is achieved without the complex two-layer construction shown in
U.S. patent 5,776,583. In that construction, each cell constitutes a bottom
hollow portion which holds all of the liquid. Complex features are required to
sustain this two-layer structure. By contrast, the surface 10 disclosed herein
distributes liquid from the point of origin of a spill through distribution
channels
24 sized, shaped, and positioned to keep the liquid being distributed between
cells 16 from coming in contact with an object resting on the surface 10.
It will be appreciated that the dimensions of the cells 16, walls 18, wells
22, channels 24, and tops 26 can be varied according to the circumstances in
which the surface 10 will be used. For example, in circumstances where spills
are likely to happen quickly, with substantial amounts of liquid involved, it
is
better to have wells 22 that are deeper, and distribution channels 24 having
greater flow capacities. The reason for this is that with quick, high volume
spills,
a low-capacity well and/or distribution channel may be overwhelmed by the
CA 02809741 2013-03-15
13
volume and speed of the spill, thus causing liquid to flood over the walls 18,
and
possibly, over the perimeter wall 12, which is undesirable. The wells 22 and
channels 24 need sufficient capacity to handle spills that are likely to
happen in
the intended application, so the surface 10 may control the spill and also, so
the
liquid will not be undesirably deposited on the tops 26 so as to come into
contact with objects resting on the surface 10. On the other hand, where
individual spills are likely to contain low liquid volumes, or to be slow
spills or
leaks, it is preferable to have wells are that shallower. The reason is that
deeper, higher-capacity wells require a thicker surface 10. This in turn
results
in a surface that is heavier, and uses a larger amount of material. Unless
this
extra material is required, for example, for the reasons described above, it
is
preferable to use less material and incur less expense for materials, as well
as
to have a surface 10 that is as lightweight and easily manipulable as
possible.
Figures 15 and 16 show a further embodiment of the invention. In the
surface 10 of Figures 15-16, a portion of a surface 10 is shown. The surface
includes a perimeter wall 12, formation 14, and cells 16 as described above.
However, one section of the surface 10 within the perimeter wall 12 is
reserved
for a reservoir 28 having a removable cover 30. The top portion of the cover
30
presents a plurality of reservoir drains 32, through which liquid travels
through
the cover 30 to the reservoir 28. Contained within the reservoir 28 is an
absorbent material 34 (e.g. a sponge or desiccant body). Liquid can also enter
the reservoir 28 from cells 16 adjacent thereto, travelling through reservoir
channels 36. The absorbent material 34 has absorbent material channels 38
which are positioned to line up with the reservoir channels 36. Preferably,
the
absorbent material channels 38 do not extend through the entirety of the
absorbent material 34. Rather, the absorbent material channels 38 preferably
function to direct liquid received from adjacent cells 16 to a central portion
of the
absorbent material 34.
CA 02809741 2013-03-15
14
The cover 30 preferably rests in a cover recess 42 formed in the
perimeter wall 12. This embodiment of the surface 10 further includes a
selectively openable and selectively closeable gate drain 40, connecting the
reservoir 28 to the outside of the surface 10 through the perimeter wall 12.
Most
preferably, the drain takes the form of a sliding gate which can be actuated
by
the fingers of the user of the surface 10. As another possibility, a drain may
be
employed in the base of the surface, and act automatically, for a like
purpose.
Such a drain in the base of the surface may be positioned so as to drain
liquid
from the reservoir 28.
It will be appreciated that the reservoir 28 is useful in situations where the
surface is being used on an inclined surface. In such situations, liquid is
much
more likely to travel toward the lower end of the surface 10 and collect
there.
In situations where the incline is steep enough, the liquid may spill over the
perimeter wall 12 at the lower end of the surface 10. The reservoir 28 is thus
useful for collecting such liquid and holding it within the reservoir 28,
preferably
in the absorbent material 34. Using the selectively openable and closeable
reservoir drain 40, the liquid collected in the reservoir 28 can be removed,
and
the absorbent material changed or squeezed out for reuse.
It will be appreciated that the reservoir may take other forms besides that
described above, and still be comprehended by the invention. For example, the
reservoir 28 need not have a drain 40 as described: liquid can be removed
simply by pouring it out and/or squeezing the absorbent material.
Alternatively,
a reservoir 28 may be employed without the use of absorbent material 34, if
the
liquid is not likely to enter the reservoir 28 at a high enough volume to
require
absorbent material 34.
In addition, the reservoir 28 may be used without reservoir drains 32. In
some circumstances, it may be desirable for the reservoir to collect liquid
only
from adjacent cells 16. It will be appreciated, however, that, in the
preferred
embodiment, reservoir drains 32 are used so that if liquid spills onto the
cover
30, it will be collected by the surface 10, and in particular, the reservoir
28.
CA 02809741 2013-03-15
15
From these examples, it will be appreciated by those skilled in the art that a
reservoir 28 may, depending on the circumstances, be employed without the
specific other features described herein in association with the reservoir.
In some applications, it may be desirable to configure the surface 10 so
that liquid flows more toward one section of the surface and away from
another.
This can be achieved in a number of ways. For example, wells 22 of cells 16
in one or more sections of the surface can be made shallow to cause liquid to
flow away from these sections more quickly to liquid retaining sections of the
surfaces whose cells 16 have deeper wells 22. As another example, the surface
10 may have a base whose thickness varies depending on the location on the
surface. The result is that some cells to be higher than others, and causing
liquid flow from the higher cells 16 to the lower cells 16. One use of such a
feature is to cause liquid to flow away from a portion of the surface 10 where
an
object is likely to contact the surface 10, thus providing further protection
against
the possibility that liquid will be transferred from the surface 10 to the
object.
It will be appreciated that a drain can be fitted in the base of the surface
10 to drain liquid from one or more of the cells 16, even in configurations
lacking
a reservoir 28. Such a drain can be useful in configurations, just described,
in
which liquid is encouraged to flow away from certain portions of the surface
and
to others.While the foregoing embodiments of the present invention has been
set
forth in considerable detail for the purposes of making a complete dislosure
of
the invention, it will be apparent for those skilled in the art that various
modifications can be made to the device without departing from the broad scope
of the invention as defined in the attached claims. Some of these variations
are
discussed above and others will be apparent to those skilled in the art. For
example, a wide variety of different shapes for the walls 18 and tops 26 are
possible within the scope of the attached claims. As another example, the
surface 10, while preferably generally rectangular in plan view, can be any
convenient shape. Similarly, the cells 16, while generally rectangular in plan
CA 02809741 2013-03-15
16
view, can take other shapes (e.g. as shown in Figures 4 and 5). What is
important is to provide a surface 10 for controlling liquids.
