U.S. patent number 3,681,882 [Application Number 05/023,531] was granted by the patent office on 1972-08-08 for raised floor panel and assembly.
This patent grant is currently assigned to United Fabricating Company, Inc.. Invention is credited to James H. Bettinger.
United States Patent |
3,681,882 |
Bettinger |
August 8, 1972 |
**Please see images for:
( Certificate of Correction ) ** |
RAISED FLOOR PANEL AND ASSEMBLY
Abstract
Disclosed is a raised floor panel and panel assembly for
computer and similar installations. The panels are supported above
a subfloor on pedestals and are easily installed and removed for
later access to the space beneath the floor. Each panel comprises a
core with or without strengthening metal sheets about which is
wrapped a flexible and at least partially resilient floor covering,
such as carpet or flexible tile material. The floor covering
extends over the edges and for a short distance beneath each
panel.
Inventors: |
Bettinger; James H. (Elkridge,
MD) |
Assignee: |
United Fabricating Company,
Inc. (Elkridge, MD)
|
Family
ID: |
21815667 |
Appl.
No.: |
05/023,531 |
Filed: |
March 30, 1970 |
Current U.S.
Class: |
52/126.6; 52/600;
52/273 |
Current CPC
Class: |
E04F
15/02452 (20130101); E04F 15/0247 (20130101) |
Current International
Class: |
E04F
15/024 (20060101); E04b 005/43 () |
Field of
Search: |
;52/126,273,177,390,599,600,267 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hunter; Hampton
Claims
What is claimed and desired to be secured by United States Letters
Patent is:
1. An elevated floor assembly comprising a subfloor, a plurality of
pedestals spaced about said subfloor, and a plurality of floor
panels supported by said pedestals in spaced relation above said
subfloor, each panel comprising a rectangular core having top and
bottom surfaces joined by four edges, a flexible and at least
partially resilient floor carpet integrally overlying said tip
surface and said edges of said core, portions of said carpet on
adjacent panels overlying said edges being in abutting contact with
each other, said carpet also extending integrally along said bottom
surface of each of said cores adjacent each of said edges, said
panel having a thickness on the order of 1 to 2 inches with
sufficient strength for use as a flooring in said elevated floor
assembly, and static electricity discharge means engaging the
portions of said carpet extending along the bottom surface of the
core of at least some of said panels whereby static electricity in
the carpet of said panels may be discharged through both said
discharge mans and the abutting carpet surface of adjacent
panels.
2. An assembly according to claim 1 including a grid of metal
stringers spacing said panels from said pedestals.
3. An assembly according to claim 1 wherein said pedestals directly
support said panels above said subfloor.
4. An assembly according to claim 1 wherein each of said cores is
of square cross section.
5. An assembly according to claim 1 wherein each of said cores is
made of non-metallic material, each panel including a metal sheet
overlying each of said top and bottom core surfaces, said sheets
extending between said carpet and the respective surfaces of said
cores.
6. An assembly according to claim 1 wherein each said core is made
from material selected from the group consisting of wood particle
board, gypsum board, plywood, light-weight concrete, and
light-weight concrete including metal reinforcing.
Description
This invention relates to raised floor panels and to raised floor
panel assemblies, and more particularly to apparatus of this type
of simplified and inexpensive construction which reduces the cost
of manufacturing and assembling raised or elevated floors.
Modern computer installations employing advanced computer equipment
require a carefully planned and completely coordinated environment.
Today's sophisticated equipment must be provided with temperature
and humidity control, air filtration, traffic and noise
restrictions, and a wide variety of other flexible facilities for
the machines and their operators. Provision must be made for future
expansion, in the form of new or modified equipment.
For these and other reasons, many modern computer installations are
provided with what are commonly referred to as raised or elevated
floors. These floors generally take the form of removable
rectangular floor panels or tiles supported in spaced relation
above a suitable subfloor by a metal lattice of criss-crossing
grids and supporting columns. Conduits, such as electrical cabling,
air conditioning equipment, and the like, pass between the subfloor
and the floor to the computer circuits and associated equipment. In
some instances, the space between the tow floors may be used as a
plenum to supply conditioning air to various parts of the room. In
all cases the removability of the panels provides great flexibility
in making it possible to add additional cabling or to service the
computer equipment as the need arises.
The present invention is directed to an improved panel and panel
assembly for raised floors of this general type and is particularly
directed to a construction which substantially lessens the cost of
manufacturing and installing the floor. In the present invention,
the customary floor tile covering for the panels and the
accompanying lateral trim edge is replaced by a flexible and
preferably at least slightly resilient floor covering material
which not only extends over the top surface of the floor panels,
but also along the edges and preferably for a short distance along
the underside of each panel. In the preferred embodiment, the floor
covering takes the form of a carpet with sufficient resiliency that
the abutting edges of adjacent panels form an air seal to define a
plenum beneath the raised floor. An important feature resulting
from the use of a flexible floor covering material extending over
the top and side edges of the panels is that the panel cores need
not be held to close tolerances and materials such as light weight
concrete may be used as the cone. At the same time, the resiliency
of the carpet material permits slight adjustment for variations in
panel size from panel to panel and further provides for easy
installation and removal of the panels due to the resiliency with
which they abut. Additional advantages include the fact that the
flexible and resilient nature of the carpeting material achieves a
sound dampening and cushioning feature for the floor system by
eliminating any metal-to-metal contact and the utilization of a
continuous cover material eliminates static electricity buildup in
the walking surface of each panel by allowing the static
electricity buildup to follow a natural path to ground. Since the
wraparound floor covering material is in contact with the metal
understructure which is conventionally connected at spaced points
to a central grounding system, all static electricity is conducted
to ground.
It is therefore one object of the present invention to provide an
improved panel for raised floors.
Another object of the present invention is to provide an improved
raised floor system of simplified and less expensive
construction.
Another object of the present invention is to provide an improved
panel and raised floor system which substantially reduces the cost
of manufacturing and installing the floor.
Another object of the present invention is to provide an improved
panel and floor panel assembly permitting the use of a wide variety
of panel cores which need not be manufactured to close
tolerances.
Another object of the present invention is to provide a raised
floor panel and panel assembly in which the top surface and side
edges of the panels are each covered by an integral layer of floor
carpeting.
Another object of the present invention is to provide a raised
floor panel in which a conventional pile carpet extends over the
top, along each side edge, and for a short distance along the
bottom and round the entire periphery of each panel.
Another object of the present invention is to provide an elevated
or raised floor panel system in which each panel comprises a
concrete core covered on at least all but one side by a flexible
and resilient floor covering material, such as carpeting or the
like.
These and further objects and advantages of the invention will be
more apparent upon reference to the following specification,
claims, and appended drawings, wherein:
FIG. 1 is a perspective view of a portion of a raised floor
assembly constructed in accordance with the present invention;
FIG. 2 is a partial cross section through the raised floor assembly
or system of FIG. 1;
FIG. 3 is an enlarged view of a support pedestal, grid, and
abutting panel junction in the system of FIGS. 1 and 2;
FIG. 4A is a perspective view showing the top and two side edges of
a floor panel;
FIG. 4B is a similar perspective view showing the bottom and other
two side edges of the panel of FIG. 4A;
FIG. 5 is a perspective view of a modified floor panel with parts
cut away to show the carpet attached directly to the core;
FIG. 6 is a partial elevational view corresponding to that of FIG.
3 showing a portion of a raised floor assembly in which the metal
gridwork is omitted;
FIG. 7 is a partial cross section through a modified floor panel
constructed in accordance with the present invention;
FIG. 8 is a partial cross section through a further modified floor
panel constructed in accordance with this invention; and
FIG. 9 is a view similar to FIGS 3 and 6 showing a still further
modified elevated floor assembly.
Referring to the drawings, a portion of a raised floor system
constructed in accordance with the present invention is generally
indicated at 10 in FIG. 1. The system is illustrated as under
construction in a room including walls 12 and 14 and a subfloor 16.
Adhesively secured or otherwise suitably attached to the subfloor
are a plurality of pedestals 18 in the form of adjustable metal
column supports for a plurality of identical rectangular floor
panels 20. Some of the panels 20 in FIG. 1 are omitted to show the
underlying support pedestals 18 and the overall metal grid
generally indicated at 22. The grid 22 comprises longitudinal and
transverse grid members or stringers 24 and 26 supported by and
preferably attached to the heads or caps of each of the pedestals
18. Various pedestal and grid constructions are presently available
and any of the well known structures may be used in the present
invention. In the preferred embodiment, pedestals 18 are placed on
24 inch centers and the panels 20 are preferably square and
approximately 2 feet on each side.
Referring in particular to FIGS. 2 and 3, pedestals 18 each
comprise a base 28 welded, brazed, or otherwise suitably secured as
indicated at 30 in FIG. 3 to one end of a threaded metal stud 32.
The upper end of stud 32 is received in the hollow lower end of
metal tube 34. The upper end of this tube is again welded, brazed,
or otherwise suitably attached as at 36 to the underside of a
pedestal cap or head 38. The telescoping relationship between stud
32 and tube 34 may be adjusted by a pair of metal leveling nuts 40
and 42 to vary and adjust the height of the pedestal 18. Base 28 of
the pedestal is preferably attached to subfloor 16 with adhesive
but may be secured in any desired manner. Likewise, cap 38 of the
pedestal may be attached to the stringers 24 and 26 in any
conventional manner. In some systems, the pedestal head includes
projections over which the stringers are slidably received to
secure and lock the stringers to the pedestal. In other
constructions, the stringers are attached by bolts and nuts to the
head of the pedestal. In the embodiment shown, the stringers 24 and
26 are preferably all of equal length, i.e., nominally 2 feet, and
are slid over suitable projections on the head of pedestal. It is
understood that the present invention is equally applicable to
other grid assemblies in which the stringers are bolted to the
pedestals and in which individual integral stringer elements may
span more than two adjacent pedestals, i.e., may be 4 feet or more
in length.
Resting on the stringers 24 and 26 nd forming made important part
of the present invention are the novel floor panels 20. Each panel
is identical in construction and preferably each is 24 inches on a
side to have a square configuration on the order of 1 to 2 inches
thick. As best seen in FIG. 3, each of the panels comprises a core
50 approximately 1 inch thick and made of suitable material, such
as a high density particle board, i.e., compressed wood particles.
Overlying the upper and lower surfaces of core 50 are flat
rectangular sheets 52 and 54 preferably made of galvanized steel.
Steel sheets 42 and 54 are preferably secured to the opposite
surfaces of panel 50 by a suitable adhesive layer (not shown).
Finally, the top or walking surface of the panels 20 is formed by a
layer 56 of flexible and preferably somewhat resilient material,
which by way of example only may take the form of a conventional
all wool looped pile floor carpeting. The carpet extends integrally
with the layer 56 over the edge of the panel as indicated at 58 and
for a short distance along the panel bottom as indicated at 60. It
is understood that the carpet 56 extends integrally over all four
edges of the panel and includes a bottom portion 60 along each of
these four edges, in all instance integral as illustrated in FIGS
4A and 4B. The carpet is preferably secured to the metal plates and
to the edges of the core by suitable adhesive (not shown).
While the covering material is preferably conventional floor
carpet, it is apparent that other flexible and at least slightly
resilient materials may be used, such as certain tiles and at least
partially resilient vinyl materials possessing sufficient
flexibility to be wrapped around the side edges and the bottom of
the panels. Adhesives which may be used to bond the steel sheets to
the cores and to bond the carpet or other floor covering material
to the remainder of the panels include conventional two-part epoxy
adhesive and conventional rubber-base, two surface adhesives with
contact bonding at both surfaces. In certain instances, where load
requirements permit, the steel sheet 52 and 54 may be omitted and
the carpet 56 bonded directly to the core 50.
An important feature of the present invention includes the fact
that the resiliency of the covering material 56 wrapped around the
edges and the underside of the panels makes it possible to utilize
a variety of core materials which were unsuited to prior raised
floor panels due to the close panel tolerances which had to be
maintained. That is, the resiliency of the covering material at the
abutting edges of adjacent panels 58 automatically compensates for
variations in core sections 50 from panel to panel such that a
variety of core materials may be used, some of which while having
exceptional strength are difficult to manufacture in quantity
within the tolerances previously necessitated by the metal edge and
vinyl trim strip constructions of previous raised floor panels. For
example, FIG. 6 shows a construction in which the floor panels 70
are of identical construction to the panels 20 previously described
but with the exception that the cores 72 are made of lightweight
and preferably expanded concrete. Because of the increased strength
afforded by the concrete cores and where loading requirements
permit, the grid assembly 22 can be omitted and the pedestals 18,
which in this case are provided with a flat cap or head 74,
directly support abutting panels 70. The result is a substantial
savings in the cost of manufacturing and assembling the raised or
elevated floor.
FIG. 7 shows a modified panel 80 in partial cross section in all
respects identical to the panels 70 of FIG. 6 with the exception
that the concrete core 82 has embedded in it interconnected
longitudinal and transverse strands 84 and 86 of metal reinforcing
rods to provide added strength to the core and overall panel. FIG.
8 shows a still further modification and illustrates in partial
cross section a panel 90 identical to the panels previously
described but in which the core 92 is formed of several
interconnected wood plies to form a plywood core of increased
strength.
FIG. 9 shows a further modified panel and panel assembly with like
parts again bearing like reference numerals. In the embodiment of
FIG. 9, the panels 20' are in all respects identical to the panels
20 previously described with the exception that each of the edges
has a very noticeable taper, as indicated at 94, from the top to
the bottom surface of the panel. The panels previously describe are
all preferably made with a slight taper from top to bottom to
reduce the friction encountered when the panels are inserted and
particularly when they are removed from adjacent panels. This taper
has not been described in connection with the previous embodiments
since it is fairly slight and in any event is obscured by the
resilient nature of the floor covering material when the edges of
two panels are in abutment. The slight taper is indicated generally
at 88 in FIGS. 7 and 8. In the embodiment of FIG. 9, the taper 94
is much more pronounced to provide clearance for a rib 96 formed
along the top edge of the stringers, such as the stringer 26'
illustrated. In this embodiment, the pedestal 18' is also modified
to include an outwardly flaring head 98 suitably apertured to pass
four screws (only one of which is indicated at 100) for securing a
bracket or nut 102 to the end of the stringer 26'. To attach the
stringer to the head, the stringer is slipped into position with
its lower flanges resting on head 98 but beneath nut 102. Screw 100
is then tightened to clamp the stringer by the nut to the top of
the pedestal head. It is understood that the other three stringers
forming a corner junction for the assembly of FIG. 9 are similarly
secured to he pedestal 18'. A ground wire 104 is provided with a
conductive eyelet 106 electrically connected to the metal stringer
26' by a second screw 108 and nut 110, screw 108 passing through a
suitable aperture provided in the stringer. The other end of ground
wire 104 is connected to the central building ground system and one
such wire 104 is preferably provided for each 1,000 square feet of
elevated floor area.
Important features of the present invention include the provision
of elevated floor panels in which a flexible and at least partially
resilient floor covering material extends over the top of the panel
and over the side edges and around the outer portion of the panel
bottom. This makes possible the use of a variety of panel core
materials since the resiliency and flexibility of the covering
material, particularly about the abutting edges of adjacent floor
panels, automatically compensates for variation in size of the core
and makes possible the use of core materials which could not
previously be economically manufactured to the required tolerances.
In addition to the more conventional fiberboard and pressed wood
particle board panels, the present invention makes possible the use
of other core material, such as gypsum board core, lightweight and
preferably expanded concrete, either reinforced or not reinforced,
and laminated wood paneling cores or plywood cores may also be
used. In the preferred embodiment, the panel covering material
takes the form of a conventional pile carpet made of wool, Nylon,
or any of the other conventional carpet materials. Since stronger
core materials, such as the newer lightweight concrete, may be
employed, the floor panels of the present invention may be provided
with increased strength in certain instances permitting the
elimination of the conventional metal gridwork so that the panels
are directly supported on pedestals as illustrated in FIG. 6. The
panels are preferably of square configuration approximately 24
inches on a side and may vary in thickness from approximately 1 to
2 inches or more, depending upon the panel size, panel material,
and the loads to be supported. In certain instances, the covering
material may be applied directly to the cores but where additional
strength is required, the panels may be provided with the upper and
lower preferably galvanized metal sheets 52 and 54.
The resilient nature of the covering makes it possible to readily
insert and remove a panel in spite of small variations in size from
panel to panel since the cushioning outer cover material along the
panel edges tends to give as the panel is inserted and removed. In
addition, the cushioning action of the covering material extending
along the four edges at 60 on the under side of the panel provides
a cushioning effect when the panel rests on the head 74 of FIG. 6
or on the stringers, such as the stringer 26 of FIG. 3, so that
there is no direct metal-to-metal contact between the stringer or
head and the metal sheet 54. At the same time, the resilient
engagement of this lower edge 60 of the panel with the support
member and the similar engagement of the side edge 58 with an
adjacent panel provides a multiple seal acting to seal the air
space between the panels forming the elevated floor and the
subfloor 16 so that this space, which may vary from a few to
several inches in height, may be used as a plenum for supplying air
to various locations in the room. Finally, the integral nature of
the wraparound floor material provides a natural path to ground
through the floor carpet itself to eliminate static electricity
buildup in the walking surface of each panel. By virtue of the
wraparound floor covering in contact with the metal understructure,
through lower edge 60 and the metal understructure being connected
at appropriate points to a central grounding system as illustrated
at 104 in FIG. 9, all static electricity tends to go to ground.
This is an important consideration for many computer installations
since static discharge is considered harmful to the low voltage
equipment employed in these installations. If desired, the carpet
material may be of the well known anti-static type so as to further
reduce the likelihood of static buildup and discharge which might
otherwise result from the motion of people, carts, furniture, etc.,
in contact with the floor covering material. Abrupt discharges of
the static charges to metallic surfaces or other people can cause
discomfort to personnel and may cause malfunction of the low
voltage electronic equipment.
This invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof. The
present embodiments are therefore to be considered in all respects
as illustrative and not restrictive, the scope of the invention
being indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are therefore intended to be
embraced therein.
* * * * *