Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to metal plank grating of the
type used in the construction of flooring and subflooring and
particularly in mezzanine decks that are erected in warehouses
and other buildings.
The utilization of storage space in warehouses and
similar buildings can often be made more effective by con-
structing a me~zanine level deck at a location intermediate the
floor and ceiling of the building. The mezzanine provides
added floor space at a convenient location that formerly served
only as vacant overhead space. The mezzanine provides
expansion space without the need to incur the high costs of new
building construction.
The mezzanine structure is typically supported by
horizontal beams that extend between upright support columns
standing on the warehouse floor~ Decking is installed on the
horizontal beams to form the mezzanine floor. Connected metal
planks, which can be either solid surfaces or gratings, are
most often used to form -the decking. Assembly of the decking
normally involves the application of nuts and bolts, crimping
of overlapped flanges or similar mechanical fasteners that
require tools and the installation costs are relatively high
due to the need to connect the planks together. Other problems
with conventional plank grating is that the strength is not
always sufficient to accommodate the heavy loads that can be
applied to the mezzanine deck or to the conventional decks
easily applicable for wheel use.
The present invention is directed to an improved
plank grating assembly. It is the principal object of the
invention to provide a plank grating arrangement which can be
quickly and easily assembled, withou-t the need for tools or
mechanical fasteners, and which exhibits the strength required
by accepted design criteria. Other objects of the invention
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include the provision of a plank grating assembly which is
economical to manufacture, which readily accommodates wheeled
goods on the deck surface, and which is constructed to utilize
a vari.able number of cross braces so that different load
capacities and concentrated loads can be handled. It is
another important object of the invention to provide a plank
grating assembly in which the loads are uniformly distributed
and effectively transmitted to the main support beams.
In accordance with the invention, the decking is
formed by longitudinal planks which are connected with one
another and supported by cross braces each having the shape of
an inverted V. The cross braces are slotted on both ends and
are slipped through openings formed in side flanges of the
longitudinal planks. The braces can be rotated into an
assembled position in which they lock the flanges of adjacent
planks together in order to rigidly connect the planks side by
side to form a continuous deck surface. The braces are located
immediately beneath the deck surface in order to receive and
transmit the loads applied to the deckO The load bearing
braces not only transmit loads from the planks to the support
beams in an efficient and uniform manner, but they also ri.gidly
connect adjacent planks without using male or female type
flanges, without the need to install nuts and bolts or other
special fasteners and without the need -for crimping tools or
other assembly equipment.
In the accompanying drawings which form a part of the
specification and are to be read in conjunction therewith and
in which like reference numerals are used to indicate like
parts in various views:
Fig. 1 is a fragmentary perspective view of a floor,
subfloor or mezzanine deck cons-tructed in accordance with the
plank grating arrangement of the present invention, with a
portion of the deck broken away for purposes of illustration;
Fig. 2 is a fragmentary side elevational view oE the
deck on an enlarged scale taken generally along line 2-2 of
Fig. 1 in the direction of the arrows, and
Fig. 3 is a fragmentary sectional view on an enlarged
scale taken generally along line 3-3 of Fig. 1 in the direction
of the arrows, with the broken away portions indicating
continuous length.
ReEerring now to the drawings in more detail, the
present invention provides plank grating which can be used to
construct decking, flooring and/or subflooring. For purposes
of illustration, a portion of a mezzanine cleck 10 is shown in
Fig. 1 in order to exempliEy the types of decking or flooring
that can be assembled by using the plank grating.
The plank grating assembly includes a plurality of
metal planks 12 which are connected and supported by ties or
braces 14. Both the planks 12 and braces 14 are constructed of
steel, and they can be conveniently formed by continuous roll
forming production techniques utilizing pre-coated coils oE 18
gauge steel, for example.
Planks 12 can vary in length, although it is
contemplated that each plank will be between 12 and 24 feet
long. The width oE each plank can also vary and is 11 3/4
inches in a preferred form of the invention. The body portion
of each plank 12 provides a deck panel 16 having a series of
longitudinal grooves 18 (which may help provide a roughened
upper surEace) therein to strengthen the deck panel and prov;de
a non-skid surface. Each of the opposite side edges of the
deck panel 16 is provided with a downturned side flange 20
having a height of 2 1/2 inches in the preferred form of the
invention. Turned inwardly from the bottom edge of each Elange
20 is a shorter horizontal flange 22 which is parallel to the
deck panel 16. An upturned lip 24 is forrned on the lnside edge
of each bottom flange 22 and should be dimensioned so that it
will not tc>uch cross brace 140
As best shown in Fig~ 2, each side flange 20 of each
plank is provided with a plurality of spaced apart openings 26
each having a trapezoidal shape. The upper and lower edges 28
and 30 of each opening are generally parallel, although the
bottom edge 30 is provided with a centra]ly located projection
32 which defines recessed areas 34 on either side of the
projection. The side edges 36 of each opening 26 are inclined
in opposite directions and converge slightly from bottom to
top. In a preferred form of the invention, the lateral
dimension between the center lines of the recessed areas 34
within each opening 26 is approximately 3 inches. The vertical
dimension of each opening between the upper and lower edges 28
and 30 is about 1 1/4 inch. The length of projection 32 is 1
1/2 inches. Round holes 38 are punched between each pair of
openings 26 to serve as guides for cutoff points and/or bolt
holes if bolts are used to connect the planks.
As previously indicated, the braces 14 tie planks 12
together and receive the loads that are applied to the deck
surEace formed by the planks, ultimately transmi-tting the ]oads
to the main support beams (not shown). Each brace 14 is about
12 1/4 inches long so that it can span plank 12 between the
side flanges 20. As best shown in Fig. 2, each brace 14 is in
the form of an inverted V in section and includes a pair of
legs 40 which are connected with one another at an apex 42 of
the brace. Opposite the apex 42, each leg 40 has a free edge
44. The edges 44 are spaced apart about 3/4 inch in a
preferred form of the invention. ~he height dimension of each
brace 14 is about 2 inches.
With particular reference now to FigO 3, each brace
14 is provided in its apex 42 with a pair of tapered slots 46
located near the opposite ends of the brace. Æach slot 46
tapers as it extends downwardly from the top edge of the
brace. Each slot terminates in a flat base portion having a
width substantially equal to the combined thickness of two
plank flanges 20. Accordingly, the upper edges 28 of two
adjacent openings 26 fit closely in slot 46, as shown in Fig.
3.
The free edge 44 of each brace leg 40 is provided
with a pair of tapered slots 48 located near the opposite ends
of the legs. Slots 48 are not as deep as slots 46. Slots 48
taper as they extend upwardly into the legs, and each slot
terminates in a flat base portion equal in width to the
combined thickness of two flanges 20. The lower edges 30 of
adjacent openings 26 thus fit closely in slot 48 in the manner
shown in Fig. 3.
Each leg 40 of each brace 14 is provided with a
series of holes 50 which permit the assembled plank grating
structure to be tied down to its supporting structure (not
shown); or it may serve as a passageway for conduit to assist
light fixture installers.
In order to assemble the planks 12 for the formation
of the mezzanine deck 10, each plank is positioned side by side
with an adjacent plank such that the adjacent flanges 20 are
disposed flatly against one another~ as shown in Fig. 3. The
openings 26 in the adjacent flanges are aligned with one
another and with the openings in the flanges on the opposite
sides of the planks. With the planks so positioned, a brace 14
is inserted through the aligned opening with the brace
positioned sideways such that its height dimension is oriented
parallel to the lateral dimension of the openings. Since the
openings are each greater than 3 inches wide and the height of
each ~race is 2 inches, the brace can be easily Eitted through
the openings in this orientation to span the opposite flanges
of the selected plank 12. When slots 46 and 48 are disposed in
the same plane as the upper and lower edges 28 and 30 of the
openings, the brace is rotated through 90 to the assembled
posi-tion in Fig. 2 wherein the height dimension of the brace is
oriented parallel with the vertical dimension of the opening.
The upper edyes 28 of adjacent openings 26 then fit closely in
the upper slot 46, while the adjacent lower edges 30 fit
closely in the lower slot 48. The slots 46 and 48 on che
opposite end of -the brace receive another pair of upper and
lower edges, unless the plank extends along one side of the
deck. Then, only one upper edge 28 and one lower edge 30 are
received in the slots 46 and 48.
In the assembled position, the apex 42 of each brace
extends immediately beneath the deck panel 16 to provide
bracing and supportO The free edges 44 of the brace legs 40
rest on top of the lips 24 to provide Eurther stability. The
distance between the base portions of slots 46 and 48 is equal
to the vertical dimension of opening 26 so that a close fit is
achieved. The side edges 36 of openings 26 are inclined in
conformity with the incline of the brace legs 40.
Consequently, when one of the braces is in the assembled
position adjacent to one of the side edges 36, the adjacent leg
40 is positioned adjacent to the side edge of -the opening as
shown in Fig. 2. The legs 40 span recesses 34 and fit closely
therein to resist any tendency for the legs (40) to unduly
spread apart when loads are applied to the deckingO In this
manner, the brace is firmly held in position to connect and
support the planks. The assembled plank grating can be mounted
in any suitable manner to conventional mezzanine support beams.
When applied in this manner to the longitudinaL
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planks 12, the cross braces 14 are oriented transversely to the
planks and are rigidly interloc)ced therewith. The braces serve
to rigidly connect the adjacent planks together side by side in
order to provide a continuous deck surface for the me~zanine or
flooring formed by the plank grating. At the same time, the
braces receive the loads that are applied to the planks and
transmit the loads in a uniform manner from the planks to the
support beams (not shown).
It is noted that the number of braces that are
utilized per linear foot of planking can be varied as desired,
depending upon the load requirements. ~'he braces 14 can be
spaced rather widelyj or they can be installed in each
opening. It is an important fea~ure of ~he invention that two
of the braces can be installed in one opening 26. After the
first brace has been assembled as shown in solid lines in Fig.
2, the second brace is inserted through the openings with its
height dimension oriented parallel to the lateral dimension of
the opening. The second brace can then be rotated 90 to the
assembled position shown in broken lines in Fig. 2. This also
permits the cross braces to be installed as close as 3 inches
in adjacent planks using same opening 26. Thus, if heavy loads
are to be applied to the decking, or if particularly strong
bracing is needed at the ends of planks or at splices between
planks, it is possible to provide two braces for each of the
openings 26. More commonly, the braces will be spaced more
widely apart such as at two or three foot intervals.
When fully assembled9 the interlocked planks 12 and
braces 14 transmit the applied loads throughout all of -the
panels in a uniform and efficient manner in all directions.
The positive and negative forces interact between the adjacent
support beams (not shown~. Installation requires neither tools
nor mechanical fasteners such as nuts and bolts, and the male-
female configuration on the lower end of each side flange 20permits the planks to be interchanged and/or reversed. The
joints between plank ends will normally be staggered (such as
on 6 inch centers) and do not need to be located over the main
support beams.
From the Eoregoing, it will be seen that this
invention is one well adapted to attain all the ends and
objects hereinabove set forth together with other advantages
whlch are obvious and which are inherent to the structure.
It will be understood that certain feat~res and
subcombinations are of utility and may be employed without
reference to other features and subcombinations. This is
contemplated by and is within the scope of the claim.
Since many possible embodiments may be made of the
invention without departing from the scope thereof, i-t is to be
understood that all matter herein set forth or shown in the
accompanying drawings is to be interpreted as illus-tra-
tive and not in a limiting sense.
