Note: Descriptions are shown in the official language in which they were submitted.
1~73~ Docket ~o. 1376
SPE~CII~ICATION
CDAIR lltAT
Back~round Of The Invention
This invention relates to chair or floor mats for supporting castered chairs
or the like on a subjacent support surface or floor and, particularly, to a chair
mat which provides for easy rolling of castered chairs onto and off of the mat.
It is well known in the prior art that chair mats are placed on top of
carpeting in offices, for instance, so that` when castered furniture rolls across
the surface of the mat it does so more easily than rolling across the surface ofa carpeted floor. Most offices throughout the country use such chair mats with
carpeted flooring, &S well as to prevent the marring of other types of flooring. There have been at least two major problems with such chair mats,
particularly when used with carpeting having relatively thick pile. First, it isquite difficult to roll castered furniture onto and off of the edge of the mat.
Second, the mat edge creates a safety hazard because individuals are prone to
trip over the edge of the mat. These problems are caused because the peripheral
edges of such mats are quite abrupt.
Attempts have been made to solve these problems by attaching reinforcing
strips about the edges of the mats, the reinforcing strips often having an
approach ramp thereabout. An example of such a reinforcing strip is shown in
U.S. Patent No. 2,004,204 to Jackson. Ilowever, such reinforcing strips are
difficult to install, are prone to loosen and greatly increase the cost of the
mat. In addition, mats with such reinforcing strips are aesthetically unacceptable.
Attempts to form an approach ramp integral with the mat itself has been
unacceptable because the resulting thin mat edge becomes prone to chipping or
cracking. This is especially true since most chair mats used today are usually
made of plastic material, particularly transparent plastic material.
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Docket No. 1376
This invention is directed to solving these problems by pr~viding a new
and improved chair mat with an integral, peripheral approach ramp edge having
proven parameters whicn provide for easy rolling of castered furniture onto and
off of the mat, while still preventing chipping or cracking of the mat.
Summary Of The Invention
An object, therefore, of the Invention is to provide a new and improved
chair mat of the character described.
In the exemplary embodiment of the invention, a chair mat is disclosed
for supporting castered chairs or the like on a subjacent support surface or
floor. The mat comprises a generally planar panel having a peripheral beveled
edge defining an inclined approach ramp extending from floor level to permit
easy rolling of castered chairs onto and off the mat. The inclined ramp is
formed integrally with the panel and at an angle of approximately 11 from
horizontal. The inclined ramp terminates at the extreme edge of the mat a
distance above the bottom surface of the mat whereby the extreme edge is of
a thickness to prevent chipping or cracking.
In the preferred embodiment, the chair mat is fabricated of plastic or
vinyl material. Proven psrameters for providing easy rolling of castered furniture
-onto and off of the mat, as well as to prevent cracking or chipping of the mat,
includes forming the inclined ramp whereby the extreme edge of the mat is of
a thickness on the order of .035 inch. As stated, the beveled edge is formed at
an angle on the order of 11 from horizontel. The width of the inclined ramp is
on the order of .625 inch. These dimensional parameters have been used
successfully with a mat having a panel thickness on the order of .135 inch.
The resulting mat no~ only provides an essy approach ramp about the periphery
thereof and prevents chipping or cracking of the mat, but the mat itself is
aesthetically pleasing as well as providing functionality not heretofore remotely
availsble without complex snd expensive reinforcing strips, The mst is provided
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Docket :lo. l376
with projecting grippers or cleats on the underside thereof, with a marginal
area about the periphery of the mat void of the cleats.
Other objects, features and advantages of the invention will be apparent
from the following detailed description taken in connection with the accompanying
drawings.
Descriotion Of The Drawings
The features of this invention which are believed to be novel are se~ forth
with particularity in the appended claims. The invention, together with its
objects and the advantages thereof, may be best understood by reference to
the following description taken in conjunction with the accompanying drawings,
in which like reference numerals identify like elements in the figures and in which:
FIGURE 1 is a top plan view of a chair mat fabricated in accordance with
the concepts of this invention; and
Fl(~URE 2 is a fragmented vertical section, on an enlarged scale, through
an edge of the mat and taken generally along line 2-2 of Figure 1.
Detailed Description Of The Preferred Embodiment
Referring to the drawings in greater detail, and first to Figure 1, a chair
mat, generally designated 10, is provided for supporting castered furniture on
a subjacent support surface such as a floor. The mat includes a generally planar
plastic panel 12 having a peripheral beveled edge defining an inclined approach
ramp 14 extending from floor level to permit easy rolling of castered chairs
onto and off of the mat. As is common, the mat is irregularly shaped, in that
it includes a forward projecting tongue portion 16 which normally is positioned
under a desk top between the side drawer portions of the desk.
Panel 12 preferably is fabricated of plastic or vinyl material and the
inclined approach ramp 14 is formed integrally therewith. More particularly,
referring to Figure 2, panel 12 has a thickness "T" on the order of approximately
.135 inch. Inclined approach ramp 14 is formed about the periphery of the panel
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1~73~
at an angle "~" on ~he order of approximately 11 to
horizontal. The angle shown in E'i~ure 2 is illustrated
relative to the top surface of panel l2. However, the
top and bottom surfaces of the mat are mutually parallel
as well as generally para]lel to the floor so that the
angle of the inclined ramp is approximately 11 relative
to floor level.
Stil] referring to Figure 2, inclined ramp 14
terminates at the extreme outer edge of the mat a dis-
tance "H" above the bottom surEace of the mat to define
an e~tremed mat edge 18 of a finite thickness. It has
proven with plastic or vinyl material that maintaining
outer edge 18 of a thickness on the order of approximately
.035 inch, cracking or chipping of the mat is prevented
while still providing the advantages of the inclined
approach ramp. The resulting width "W" of the inclined
ramp is on the order of approximate]y .625 inch. These
parameters have been proven quite effective. Of course
however, should the thickness "T" of the mat vary, while
maintaining the angle of the inclined ramp and the thick-
ness "H" of outer edge 16, the width "W" of the inclined
ramp also would vary.
The underside of mat 10 is provided with pro-
jecting grippers or cleats 20 which prevent slippage of
the mat over a carpeted surface. ~he cleats cover sub-
stantially the entire undersurface of panel 12. However,
a marginal area 22 about the periphery of the mat, along
ramp 14 on the underside of the mat, is void of the cleats.
A machine and method for forming inclined
approach ramp 14 with precise controlled parameters are
shown in copending Canadian application, Serial No. 511,140,
filed June 9, 1986 and assigned to the assignee of this
invention.
It will be understood that the invention may be
embodied in other specific forms without departing from
the spirit or central characteristics thereof. The pre-
sent examples and embodiments, therefore, are to be con-
sidered in all respects as illustrative and not restrictive,
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and the inv~ntion is not to be limited to the de~ai].s
given herein.
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